Brand New 2015 F350 Diesel

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Apr 16, 2015
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CA, USA
Hi All, I'm totally new to this forum and I'm also totally new to the science of motor oil. So I apologize in advance if my questions are a little dumb! I've read some very good articles on breaking in my diesel and they sound very believable. Basically what the dealer tells you about 'take it and drive it' is total rubbish. From what I understand you should..Keep revs low and variable for the first 100miles. Continue to not thrash it and take it easy for 500 miles and only hook up the trailer after 1000 miles. But what I'm really interested in is when I should change the oil and which oil to use on this BRAND NEW truck? I've heard various stories from change it after the engine has turned over for a few minutes to change it at 100 or 500 or 3000. This is the first diesel engine that I have ever owned so from what I understand the break in period, initial engine oil changes etc are quite critical to the successful bedding in of the rings and the future wear of bearings and other engine parts. I live in San Diego which I would say is quite a temperate climate. By user manual says to use 13quarts of 10-30 diesel motor oil. To show my complete ignorance I don't even know what the difference is between diesel motor oil and gas engine oil! The expertise and wisdom from you experts would be greatly appreciated! I pickup me new Truck from the Dealer tomorrow afternoon Thanks in Advance for your help!
 
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Check the specifications in the manual carefully. Generally speaking, it will be a CJ-4 rated 10w-30 that you'll need. Motorcraft, Delo, Rotella, and Delvac are among the many good choices out there.
 
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Mar 21, 2004
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Get a big oil drain pan. As was already mentioned, there are many great diesel rated oils out there. Many at Wallymart. I run Rotella T6 5W40 in my Cummins diesel. Your motor oil will turn black almost immediately, 100 miles? Not to worry, it happens with all diesel engines. I would go a few thousand miles before changing. The first change will get out all the initial wear metals and loose casting material.
 

CT8

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The owners manual is your friend. Read it. Yes just drive it. Don't baby it don't abuse it. Don't believe what you read ,hear etc. How long do you keep your vehicles?
 

smcrea

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We always drive our vehicles until the wheels drop off. basically we keep them forever! This is why we buy new.
 
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I'm with the dealer on this. Don't break it in easy. It's good to get some cylinder pressure to seat the rings. We had a rule at Cummins that if an engine didn't get to full power within its first 20 minutes of running, the liners would glaze, and the rings would never seat. Maybe this was already done at the factory when the engine was first tested. But it wouldn't hurt to get on it for 5-10 seconds at a time for about 10 times to seat the rings. Bearings and roller-follower valvetrains don't need breaking in. Then change the oil and filter at about 1500-2000 miles.
 
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That truck takes 10W30 in regular service or 5W40 in severe service. Personally if I had one of those I would use Rotella T6 or M1 TDT throughout the warranty period and beyond. Motorcraft does make a 5W40 full synthetic, but it is prohibitively expensive, even for an employee.
 

smcrea

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Here's the article that I read about breaking in the truck: This article outlines the processes and prescribes a superior method for breaking in the Current Production Diesel Engine. "Breaking-in" a new diesel engine... You may immediately come up with some questions such as� Why did Ford-Diesel.com release an article about something that is a non-issue? I thought newer engines were manufactured with precision crafted parts? According to the manufacturer, there is supposed to be �no break-in necessary�? Many of the engine manufacturers claim that their engines do not require break-in. That is just pure baloney! Enough pestering and a few references to some of the Cummins shop manuals have painted a clearer picture. All engines require some kind of break-in period. This is even true with current technology. Although current technology provides the means of manufacturing engine parts with unimaginable precision, the manufacturer still falls far short of achieving the near perfect fit that a proper break-in will provide. �Break-in,� for the most part, is the allowance of the machined cylinder and ring surfaces to conform to each other�s shape during engine operation. This conforming or �mating� of ring and cylinder surfaces is the ultimate goal of a proper break-in. �Mating� these two specific parts will produce a very tight seal in each cylinder. A tight seal is very important because it prevents the escape of unburned fuel and pressurized gasses into the crankcase, while further preventing crankcase oil from entering the cylinder above the top compression ring. It is the intention of this article to help people understand more about the break-in process, and what happens or can happen during the first few thousand miles of engine operation. During break-in, a small amount of compression blow-by, oil-fuel dilution, and oil consumption will be experienced. This is perfectly normal and quite common in new engines. Although acceptable at first it is imperative that these undesirable attributes be as close to zero as possible after break-in has been completed. Although the others are important, blow-by is the primary reason the ring and cylinder wall interface has to fit together so tightly. Diesel fuel needs to be introduced into an air environment that is under intense pressure in order for it to burn without an ignition source. When the fuel burns, the gasses produced multiply the compression pressure in the cylinder. Pressurized gasses that escape by means of the compression ring / cylinder wall interface are called blow-by gases. Pressure that escapes the cylinder in this manner results in a loss of energy. Whether it is pressure lost on compression or combustion, it is unable to be utilized to drive the piston through the power stroke. This loss ultimately results in a reduction of fuel mileage and power. Today�s Diesels can take a "few" miles to fully break in. 10,000 miles is not an uncommon break-in period, especially for an engine like the Power Stroke Diesel. The reasons that break-in is such a lengthy process are generally attributed to engineering targets as well as the function of diesel combustion. In terms of engineering targets, engine manufacturers produce diesel engines to sustain high torque loads over constant and extended load intervals. In other words, very durable parts are required to hold up to the rigors of diesel operating conditions. For example, The International Truck and Engine Company employs some very special parts in their 175 - 275 hp engines. The pistons used in these engines are manufactured from lightweight aluminum alloy, and are constructed with Ni-Resist ring inserts. The aforementioned piston combination is further complemented with keystone plasma faced rings. These rings help reduce oil consumption and can extend the life of the power cylinder further than ordinary chromium-plated rings. While chromium-plated rings continue to be produced for both diesel and gasoline applications, they are slowly becoming old technology. They still perform well but plasma faced rings have consistently shown superior performance. When we consider the function of diesel combustion, we must first understand the engine dynamics that are associated with that process. In order for break-in to occur, a fair amount of heat, friction and resulting wear will have to take place before the compression rings will have �mated� with the cylinder walls. When the rings and cylinder wall are new, a modest amount of heat is created merely from the friction of the new rings passing over the freshly honed cylinder wall. While the heat from friction is significant, the real heat is created from combustion of fuel in the cylinder. When the fuel is burned, gasses are produced that expand and heat all of the cylinder parts. If enough fuel is introduced, the resulting combustion can create gasses that expand so much they will actually expand the cylinder wall and the compression rings. It is important to understand this because expanding these parts places additional pressure on them, which creates more friction and correspondingly more heat. This does not take into account the additional heat from combustion that will be added to the heat from friction. Heat is important to assist wear for break-in but too much can cause major problems. This is the reason we should not subject the engine to significant loading for the first 1000 miles of its operation. Loading heavily will introduce more fuel to the cylinder, and will add significant amounts of heat and pressure to the cylinder components. Couple that scenario with new rings on a freshly honed cylinder wall and we can only imagine the amount of friction and heat being produced and absorbed by the rings. Furthermore, the engine oil, lubricating the cylinder walls, will flash burn when it contacts the very hot rings. The burned oil will leave a hard, enamel like residue on the cylinder wall, commonly known as oil glazing. When the rings are permitted to operate under such high temperatures, oil glazing of the cylinder can happen very quickly. Once this glaze builds up, the only repair is a labor-intensive process that requires disassembling the engine and re-honing the effected cylinders. Oil glazing is a problem because it is typically not distributed evenly in the cylinder, and the spaces that exist between the ring and cylinder wall are either still there or new larger ones are created. Oil glazing is typically thicker towards the top of the cylinder and it builds up in the areas where heating is the greatest. The glaze has very smooth and friction free properties that do not allow it to be scraped away by the rings. This inhibits further metal-to-metal wear between the cylinder wall and rings, preventing further mating of ring and cylinder. Thus, those small gaps between ring and cylinder surface will never seal. These spaces will then allow pressurized gasses and unburned fuel to escape into the crankcase, while allowing oil from the crankcase to enter the cylinder above the top compression ring. Well why not run the engine at idle or under no load? This is bad too. It can create a similar condition to glazing. The rings need to expand a little during this initial break-in period, just not so much that they overheat and flash the engine oil. The engine needs to be moderately loaded in order to break in correctly. Running the engine under very light or no load prevents the oil film placed on the cylinder wall from being scraped away by the expanding compression rings. The rings will instead �hydroplane� or ride over the deposited oil film, allowing it to be exposed to the cylinder combustion. The oil film will then partially burn on the cylinder leaving a residue that will build up and oxidize over time. Eventually this leaves a hard deposit on the cylinder wall that is very similar to the glaze left from flash burning. My caution to those just running the engine as a normal daily driver (without some loading) and especially those who love to idle their vehicles, expect some VERY extended break-in periods (up to 30,000 miles on one I know of). Expect oil consumption forever due to oil glazing. The rings never really seat well if they cannot expand from the dynamics and heat that a load produces. Expect poor mileage due to the passing of compression and combustion gasses around the compression rings. Additionally, expect to see increased bearing wear and engine wear due to the fuel passing the rings diluting the engine oil. Thus, we can see that heavy loading and light loading can cause some major problems. Moderate loading is the key to a proper break in for the first 1000 miles. It permits the loose fitting piston rings to expand into the cylinder walls allowing them to perform double duty: First, scraping oil off the cylinder wall, and second, to create friction that will promote wearing the two surfaces to each other�s proportions. Furthermore, moderate loading will allow the rings to get hot but not to the point where it will flash the lubricating oil supplied to the cylinder walls. Once the rings and cylinder have "mated," they will have worn away a considerable amount of their roughness. They will wear slower than they did when they were new. This reduced wear rate indicates the end of break-in, and a decrease in oil consumption should be obvious to the owner / operator. Furthermore, blow-by and fuel dilution should also be reduced but may not be so obviously evident. Be aware that engines employing Plasma faced ring technology will take a longer time to break-in. These rings tend to wear far slower than chromium-plated rings. The plasma ring�s hardness allows it to wear the cylinder wall in a more aggressive manner while only polishing the ring surface. Eventually the cylinder wall wears to the shape of the ring and subsequent cylinder wear evolves to a polishing process. This extended process drastically improves the sealing potential of the cylinder, which will correspondingly reduce blow-by and the amount of physical wear on these components. Therefore, we can safely say that the plasma faced ring / Ni Resist insert combination greatly extends engine life. Unfortunately, the price of this better seal is a longer break-in period. So the big question is: How long does it take for an engine to break-in? Outside of the rings being hard as rocks and just taking their own sweet time to mate to the cylinder bores, the greatest factor is how the engine is broken-in. Most engines will be broken-in after running for some time, but some ways of breaking-in an engine are far superior to others as they are more likely to produce low blow-by and near zero oil consumption. Therefore, I will lay out some recommended DOs well as definite DON�Ts: 1. DON'T run the engine hard for the first 50 to 100 miles. It is recommended that the engine be operated around the torque peak (1500 to 1800 RPM) in high gear. This loads the engine very gently, and allows the internal parts to "get acquainted" without any extreme forces. 2. DON'T let the engine idle for more than five (5) minutes at any one time during the first 100 miles. (Even in traffic.) Remember those loose fitting rings, and possible fuel-oil dilution that were noted above? (Fuel Dilution is very common when diesels idle, even with well broken-in engines.) Well, if that fuel is allowed to contact the main and rod bearings during break in (not really good at any time), you might be looking at an engine that will always consume some oil and one that may not produce power or mileage as expected. In the first few miles of break-in, the bearings are mating to the crank, rods, etc. It is imperative during this time that the lubrication qualities of the oil remain robust. Fuel in the oil will reduce its ability to absorb shock and float the rotating parts in their bearings. Contact between bearings and journals will occur more frequently which will result in additional friction wear. This will ultimately reduce the tight tolerances between the bearings and journals. What was originally a tight fit will be sloppy and will never be able to mate properly. 3. DO drive the engine at varying RPMs and speeds until about 1000 miles. The idea is to alternately heat and cool the rings under varying RPMs. Manual transmission-equipped trucks are the best for this as they typically employ engine compression to slow the vehicle during normal operation, this constantly allows for varied RPMs. This can also be done with automatic transmissions, but it requires that you manually downshift the transmission into the lower gears while driving. Typically, most people with automatic transmissions operate their vehicles in Drive or Overdrive gear positions without making these manual shifts. When their vehicle is decelerating and the speed falls below 38 mph the transmission has little influence on engine RPM. This is because the torque converter unlocks and the auto transmission does not downshift to lower gears in the same fashion that manually shifting does. My suggestion to those with auto transmissions is to find an empty parking lot in the evening, and drive back and forth across it in the lower gears. (This can be done with standard transmission trucks as well.) Each time revving her up close to redline and letting engine compression slow it back down. This gets the rings a bit hot, but the compression braking allows the pistons to cool with high oil spray flow and no fuel load. Keep doing this for a number of runs, or until boredom sets in. 4. DO put a load on the engine at around 1000 miles, and get the thing hot! Diesels are designed to work, and in many cases, they operate best under a load. Baptize your engine with a nice "initiation load," to introduce it to hard work. Keep the revs up (but watch the EGTs), and make sure the coolant temps rise. Hooking up your trailer and finding some hills to pull works great for this. After the 1000 mile pull, just drive it normally, always making sure to let the engine get up to normal operating temps (no 1-mile trips to 7-Eleven). Towing is ok but remember to not overload and to monitor your gauges carefully erring on the side of caution. Under these conditions, I have seen most diesels completely break-in between 10-15,000 miles, and have always been able to tell that point from mileage gains. One may also notice that the "symphony" of the engine also changes slightly at this point. We know that Engine Manufacturers have built today�s diesel engines using state of the art technology. They have fashioned parts to match in near perfect fashion. We can understand, through this article, that breaking-in this modern marvel of technology is more important then the manufacturers have lead us to believe. Furthermore, we can appreciate that following their claims can result in an engine that is wrought with inefficiency, sloppy fitting parts, and oil consumption problems. Following the guidelines and warnings set forth in this article will provide anyone who desires maximum efficiency and power out of his engine many miles of trouble free operation.
 

dnewton3

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First - welcome Second - realize that you're now a member of a very diverse group of people here at BITOG, and you'll rarely, if ever, find total agreement on anything. You will find folks that agree with you, and those that don't. So if you came here to find consensus, you're in the wrong place! Third - I am a fan of dumping FF (factory fill fluids) soon to get out the residual machining stuff. However, I certainly confess to the fact that there are a bazillion vehicles out there in the world that don't get this "special" treatment, and survive and thrive for many, many years despite lacking this "advantage" in life. So it probably is much more important in terms of making you feel better, rather than being proven "better" for your engine. Fourth - you need not copy/past really long quotes; just copy/past the link and we can read it from there. Fifth - your owner's manual is a great place to start; don't over-think this. And I will note that it's been discussed many times that what is "recommended" in the owner's manual and what is "required" to satisfy OEM warranty criteria are not the same thing conceptually. You don't "need" a 5w-40 is you are "severe" in service, despite what the manual alludes to. Generally, any CJ-4 approved lube in varying grades will suffice to satisfy warranty requirements. Again - welcome!
 
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I do the same thing from my lawn mowers on up to my commercial semi trucks. Out of the gate, I operate them like I will be operating them for their entire life span. As for oil weight, every diesel engine maker, it seems, is fully on board with the 10w30 thing, even the 13. 14. 15L engine makers. They are all coming from the factory filled with 10w30. For new motors, I would just stick with a 30w oil and not overthink things. There are thousands of heavy trucks, running from Canada to the Rio Grande ( mountains, prairies, etc ), year round, grossing 80,000 lb, and doing it quite well on a 10w30 oil. I can't see any reason why a Ford PS would be any different.
 
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Don't buy a drain pan with the 3/4" hole in the top with the plastic plug that treads in. The oil flows out of the truck faster than it flows trough that little hole in the pan. I bought a galvanized 3'x4' drip pan and a 20 quart open top bowl style pan. I pull the plug and gradually move the pan on the larger drip pan as the flow slows. Wear some old clothes. I've changed the oil 8 times on my 2011 Powerstroke and still make a mess.
 
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I have never had a light duty diesel pickup truck but in my big trucks I have always hooked up to my typical heavy load and go. I've only purchased three new trucks but in each case it was moving nearly 80k lbs as I left the dealer's lot. The first one got new oil at 10k miles but the last two trucks were run 18-20k miles on the factory fill. The first two new trucks went over 900k miles without a mechanical issue and only using some oil in the higher mileage. The third was traded in at 412k but it was strong and only dropped 1 or 2 quarts on the stick at the end of a 24k oil change interval. That was a little 10.8 liter volvo. Just wanted to share my experience regarding first oil change and breaking in. Do whatever you're comfortable with.
 
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Im not familiar with Fords recommendations but as mentioned you cant go wrong following the owners manual. Break in procedures and the recommendation against towing is aimed at the drivetrain more so than the engine. Your rear axle needs time for the ring and pinion to "work harden". The gears are new and tight and generate more heat than when they are properly broken in, and towing heavy right out of the gate adds more heat and prevents the R&P from work hardening. Also, Cummins has no break in procedures nor do they recommend short changing the oil on the first oil change, although it certainly wouldn't hurt. The advice on the R&P and the engine came directly from Ram/Cummins engineers at the CMEP tour.
 
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Originally Posted By: jrmason
Im not familiar with Fords recommendations but as mentioned you cant go wrong following the owners manual. Break in procedures and the recommendation against towing is aimed at the drivetrain more so than the engine. Your rear axle needs time for the ring and pinion to "work harden". The gears are new and tight and generate more heat than when they are properly broken in, and towing heavy right out of the gate adds more heat and prevents the R&P from work hardening. Also, Cummins has no break in procedures nor do they recommend short changing the oil on the first oil change, although it certainly wouldn't hurt. The advice on the R&P and the engine came directly from Ram/Cummins engineers at the CMEP tour.
I've heard this before (about going easy on the rear diffs) but I don't understand why they aren't made better (hardened better?)from the start. For class 8 trucks in otr service, rears are under warranty for 750k miles with the only requirement of dropping the factory fill at 500k and refilling with an approved synthetic lube. Rear ends in trucks are very reliable and long lasting so I don't know why there's such concern in these modern day pickup trucks. I suppose maybe some don't spend the extra for that warranty but it wasn't too costly (last i knew anyway) so I think the majority pay and get it. I'm looking to learn...not just yapping. smile Are the pickup trucks that much more abusive on the ring and pinion? I think it was Artem who told about having to change the diff fluid on a regular basis on his Ram heavy duty. The rear diffs on heavy pickups look gigantic so I'd expect that they hold a good bit of fluid, but maybe I'm overlooking things?
 
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Originally Posted By: A_Harman
I'm with the dealer on this. Don't break it in easy. It's good to get some cylinder pressure to seat the rings. We had a rule at Cummins that if an engine didn't get to full power within its first 20 minutes of running, the liners would glaze, and the rings would never seat. Maybe this was already done at the factory when the engine was first tested. But it wouldn't hurt to get on it for 5-10 seconds at a time for about 10 times to seat the rings. Bearings and roller-follower valvetrains don't need breaking in. Then change the oil and filter at about 1500-2000 miles.
A_Harman, do they not put new engines on a dyno for awhile to make sure they are performing as specified? I thought that was the case with all heavy diesel builders but maybe it's not enough to do any ring seating (?). Have anything to share about that? By the way, back in early 2000 I took a quick tour of Cummins in Columbus, Indiana. I got there at a bad time so it was abbreviated but got to watch both N14's and ISX being assembled. It was very cool.
 
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Originally Posted By: dustyroads
Originally Posted By: jrmason
Im not familiar with Fords recommendations but as mentioned you cant go wrong following the owners manual. Break in procedures and the recommendation against towing is aimed at the drivetrain more so than the engine. Your rear axle needs time for the ring and pinion to "work harden". The gears are new and tight and generate more heat than when they are properly broken in, and towing heavy right out of the gate adds more heat and prevents the R&P from work hardening. Also, Cummins has no break in procedures nor do they recommend short changing the oil on the first oil change, although it certainly wouldn't hurt. The advice on the R&P and the engine came directly from Ram/Cummins engineers at the CMEP tour.
I've heard this before (about going easy on the rear diffs) but I don't understand why they aren't made better (hardened better?)from the start. For class 8 trucks in otr service, rears are under warranty for 750k miles with the only requirement of dropping the factory fill at 500k and refilling with an approved synthetic lube. Rear ends in trucks are very reliable and long lasting so I don't know why there's such concern in these modern day pickup trucks. I suppose maybe some don't spend the extra for that warranty but it wasn't too costly (last i knew anyway) so I think the majority pay and get it. I'm looking to learn...not just yapping. smile Are the pickup trucks that much more abusive on the ring and pinion? I think it was Artem who told about having to change the diff fluid on a regular basis on his Ram heavy duty. The rear diffs on heavy pickups look gigantic so I'd expect that they hold a good bit of fluid, but maybe I'm overlooking things?
In order to make them run cooler and quieter, new gears are lapped at the factory. But they are not lapped under the same pressures that driving creates, and towing creates even more pressure on new gear sets which generates heat. This is where work hardening comes into play, but must be done under light loads where the oil is kept to a minimum temperature. Sustained elevated oil temps are the single biggest contributor to R&P failures. I'm no expert in drivelines but I have built a few over the years and every supplier I have dealt with has strong convictions of proper break in (Yukon, Randy's R&P, Quad 4x4). I have zero experience with the build of a class 8 diff,maybe they have some better manufacturing techniques that aren't used in pickups (for cost reasons)? I have a few assumptions as to why they last so long. One big one is temperature, and I would imagine the temp on a typical class 8 rig is lower than say a 1 ton pickup even though the loads are substantially higher. Remember, a tractor has 2 diff's to distribute the load stresses (heat). Also, the ring gear is literally 2 or 3 times the size which means reduced RPM compared to the R&P in a pickup. Rpm in a diff is a big generator of heat. Also, I am guessing that each diff holds a few gallons rather than a few pints of lube. In the end, I am pretty confident the gear set of an HD tractor has no expenses spared where as the pick up world is constantly battling to bring their trucks in at the bottom line. This eventually trickles downstream to the suppliers as they battle for contracts to supply the trucks. Just some ramblings, and mostly opinions of course.
 
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@ jrmason; thanks for reply. The fact that you've done some driveline work puts you way ahead of me. I been lucky with my big trucks and never had to work on my f150's so nothing to learn from. I know that in the case of heavy duty axles, they do go to great lengths in making durable, nearly maintenance free diffs. That's just from what I've read of course, but my understanding is it has a lot to do with special hardening techniques along with excellent design for smooth meshing. I don't know how much gear lube a heavy pickup rear end takes, but golly they look huge. It seems like there is a lot of potential for a strong setup and lots of fluid. A typical class 8 rear end takes 4-5 gallons. My current truck has a single drive with a tag axle behind it as an engineered system. It's a Meritor RS23 (23k lb rating) and it does run cool (holds a full 5 gallons). So far I've seen it go as high as 126F while pushing through high winds for hours on end, but mostly stays below 109F. I haven't seen blistering summer heat yet. There again, I don't know what temp a heavy pickup rear diff runs in any case. As I mentioned in an earlier post, all three trucks that I purchased new were hooked up to a heavy load as I left the dealer. Immediately making high torque in the engine and sending it out through the entire driveline and never an issue for 900k+ miles. This is just the norm in the trucking industry. I didn't mean to bore anyone reading this to tears blush but it seems like the pickups could be built better for the crazy cost of one.
 
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There are definitely some major differences in fluid capacity and temps! The AAM 11.5 in the Ram 3500 holds 8.8 pints, or right around 4.5 quarts. Temps when towing heavy commonly exceed 180-200 degrees. Ive heard reports from guys that monitor their temps via a temp gauge that they will see spikes in excess of 225-250 when towing near max GCWR pulling a steep grade. This is the single factor (high temps)in my opinion why it s recommended to change the gear lube so frequently in pickups used for hauling. According to Machinery Lubrication, the general rule of thumb for conventional gear lube is that the rate of oxidation doubles for every 10°C (18°F) rise in temperature above 75°C (165°F). I believe this is exactly why synthetics are needed in pickups that tow and according to the temps you see in your class 8 diff's, exactly why conventional gear lube survives so long in the big rigs.
 
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Oh my! Those big diffs aren't as big as I thought. Just over a gallon of gear lube? Those are some high temps the pickups run. No wonder they require so much servicing! While there are some conventional gear lubes that are good for the 500k in trucks (at least one; delo esi) most have synthetic 75W90 in them. Again, for a reasonable fee the warranty is good for 750k with a drain and fill at 500k. Do pickup guys run off the shelf M1/royal purple gear lube? Or do they run commercial type gear lubes? I wonder if they're running gear lube purchased at their local auto parts store, if they'd be better off with a delvac, delo or shell heavy duty gear lube. I'm curious about what you guys run in pickup truck diffs.
 
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