No it does not. Wear issues with 10w30.
7.3 PSD 2002 Ford Excursion 4x4....202k...which oil?
- Thread starter va_life
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Are we talking about the same engine 7.3L?
Are you talking about the old school 7.3l PowerStroke? 15w-40 is what everyone and their brother has been running in it since forever. Ford specifies 10w-30 in the newer ones but only recommended 10w-30 for the old 7.3 in cold weather.Are we talking about the same engine 7.3L?
Wow! That is really impressive! What are your oil change intervals?
I hope my Cummins is that clean inside..
I'm sure you're correct but it's the Toyota of Diesel engine.
Running it up north probably wouldn't hurt much to run it year round?
I'm partly joking but still I do wonder if Ford spec'd 10w-30 what the overall outcome would've been. Maybe they would've never made it to legendary reliability status had they?
I had a '02 F250 w/7.3.
It had 304k on it when it was stolen.
You have made a very good purchase.
At 200k you are just getting broke in good
At 5k oci any good oil will work.
My oil of choice was conventional Rotella T 15-40.
I also switched to Rotella ELC as a coolant.
It had 304k on it when it was stolen.
You have made a very good purchase.
At 200k you are just getting broke in good
At 5k oci any good oil will work.
My oil of choice was conventional Rotella T 15-40.
I also switched to Rotella ELC as a coolant.
10k oci
I should send in my sample of Delo 10w30. Ran it all summer in my 7.3, towing a jeep in the mountains for a majority of it or being ran hard from cold for fire calls. Bought it from AutoZones clearance of it last year at $3/gal, and it was all old stock from 2019. Unfortunately I did some parts changes so I don't know how the numbers would be swayed from the breach and changing of parts of the oil system, nor did I change the filter. 7.3 didn't seem like it cared, but I did change to a 5w40.
This illustrates the problem with uncontrolled UOA that there are many influences on the results.
My 2000 7.3 has had whatever was cheapest for close to 200k and outside of fuel lines a starter and an unbelievable amount of rust has never had a bolt turned on the engine. Not the most powerful of diesels, but dam near indestructible. I’d thought about doing a total restoration but gave it to my son for his roofing business. He just replaced the starter and swapped out the group 65 Walmart value batteries that were 4 yrs old and it starts like a new truck. I think in the 20 plus years I’ve owned it, I only plugged it in a handful of times.
7.3 has the HEUI injector system, 10w30 works the best to 100 degrees.
Most 5w40s will shear to a 40 within a few miles. Most people do not use them if they want a 40wt oil and for it to stay in grade.
Amsoil AME 15w40 is known to be very shear resistant, like the old ACD SAE 30 was which was also popular in the 7.3 and 6.0 PS.
Amsoil AME 15w40 is known to be very shear resistant, like the old ACD SAE 30 was which was also popular in the 7.3 and 6.0 PS.
That’s not much shearing.
I used to own a 2002 F350 with the 7.3 made for Ford by International.What a great dependable truck it was. Between the 7.3 and the 4R100 Transmission , they were very strong and dependable. I kept the maintenance up to date as required and the truck was easy to work on. I would still have it if it hadn't rusted out to the point of the rust issues kept coming back.
I always used the MotorCraft 15w40 Oil along with the MotorCraft Oil Filter and bought these items at WM. Then, the MotorCraft Oil was made by Conoco - Phillips which was good oil. I changed the oil and oil filter every 5000 miles. The 7.3 never burned a drop of oil between oil changes. I started to lose a little oil about a quart between oil changes because of a turbo pedestal seal was leaking but when I repaired this issue, all was good. The oil filter was so easy to access. I used to use a small steel punch and punch a small hole in the oil filter to let the quart or so of oil drain out before removing the oil filter, no mess that way. I would fill the new oil filter with about a quart or so of oil and reinstall before adding the remaining oil to the crank case.
Looking back, if I still had this truck, I would have used Shell Rotella T6 5w40 during the cold months or the Motor Craft 10w30 during the cold months for weather cold protection. I would always use my timer and plug in when needed.
Currently, I own a 2011 Ram 3500 with the 6.7 Cummins, 116900 miles on it. Cummins states the oil and oil filter changes are do every 7500 or when the computer designates. My 3500 calls for the 15W40 or 5W40 at temps at Zero or below or the 5W40 can be used year round. I use the Rotella T6 5W40 year round. I change the oil and oil filter every 5000 Miles because of the emissions stuff on these trucks. The oil is pretty black after a fresh oil change because of the emissions stuff. The previous truck (2002 F350 7.3) oil really never got dirty between oil changes because of no emissions on the engine. Both the 7.3 and Cummins 5.9 - 6.7 have shown to be very dependable.
I always used the MotorCraft 15w40 Oil along with the MotorCraft Oil Filter and bought these items at WM. Then, the MotorCraft Oil was made by Conoco - Phillips which was good oil. I changed the oil and oil filter every 5000 miles. The 7.3 never burned a drop of oil between oil changes. I started to lose a little oil about a quart between oil changes because of a turbo pedestal seal was leaking but when I repaired this issue, all was good. The oil filter was so easy to access. I used to use a small steel punch and punch a small hole in the oil filter to let the quart or so of oil drain out before removing the oil filter, no mess that way. I would fill the new oil filter with about a quart or so of oil and reinstall before adding the remaining oil to the crank case.
Looking back, if I still had this truck, I would have used Shell Rotella T6 5w40 during the cold months or the Motor Craft 10w30 during the cold months for weather cold protection. I would always use my timer and plug in when needed.
Currently, I own a 2011 Ram 3500 with the 6.7 Cummins, 116900 miles on it. Cummins states the oil and oil filter changes are do every 7500 or when the computer designates. My 3500 calls for the 15W40 or 5W40 at temps at Zero or below or the 5W40 can be used year round. I use the Rotella T6 5W40 year round. I change the oil and oil filter every 5000 Miles because of the emissions stuff on these trucks. The oil is pretty black after a fresh oil change because of the emissions stuff. The previous truck (2002 F350 7.3) oil really never got dirty between oil changes because of no emissions on the engine. Both the 7.3 and Cummins 5.9 - 6.7 have shown to be very dependable.
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My previous truck 2002 Ford F350 with the 7.3 did very well with the Motor Craft 15W40 oil and the FL1995 Motor Craft oil filter, every 5000 miles. I'm not sure if Conoco Oil, still makes the Motor Craft Oil for Ford, it was decent oil. If the temperatures are really cold during the winter, the 10W30 Motor Craft Diesel Oil or any good diesel oil will work fine for cold conditions. I always used the 15W40 and plugged in on a 3 hour timer when needed.
dnewton3
Staff member
As far as the grade goes (15w-40 vs 10w-30), there is no discernable (statistically significant) difference in terms of wear control for the ol' 7.3L PSD.
Where a thinner grade can help is in extreme cold weather starts (slightly less parasitic drag on CI engines), as well as reducing the "romp" associated with HEUI systems at cold idle. If you're unfamiliar with the "romp" issue, it's when really cold oil doesn't react to the injection signal as quick as the injection driver commands it, and so the idle falls off a tad, then the driver has to compensate and commands a stronger injection event, and so it cycles up/down a bit in idle rpm, and sounds as if it's "romping". This condition isn't generally harmful, just annoying to some.
Given the OPs area, either would work fine. He's unlikely to see any benefit or degradation either way.
Where a thinner grade can help is in extreme cold weather starts (slightly less parasitic drag on CI engines), as well as reducing the "romp" associated with HEUI systems at cold idle. If you're unfamiliar with the "romp" issue, it's when really cold oil doesn't react to the injection signal as quick as the injection driver commands it, and so the idle falls off a tad, then the driver has to compensate and commands a stronger injection event, and so it cycles up/down a bit in idle rpm, and sounds as if it's "romping". This condition isn't generally harmful, just annoying to some.
Given the OPs area, either would work fine. He's unlikely to see any benefit or degradation either way.
I’ve ran 10-30 up until July in northern Ohio. It’s been years since I did but there was no issues. I just installed some 5-40 for the 1st time in 20 yrs so we’ll see how it works out. With a good starter and batteries I’ve only had to plug this truck in a handful of times and once was in northern Michigan on a snowmobiling trip when that actual temp was -13.
Motorcraft 15W-40 which is available at any Walmar.
When I owned my 2002 F350, the 7.3 ran great and was easy to maintain. I always purchased the Three 5 Quart Jugs Motor Craft 15w40 Oil and the Motor Craft FL 1995 Oil Filter at WM. I changed the oil and oil filter every 5000 miles. I used to use a small steel punch to punch a small hole in the bottom of the oil filter to drain out the approximate one quart of oil before removing the oil filter to make the oil change clean. I'm not sure who makes the Motor Craft Oil nowadays but then the Motor Craft Oil was made by Conoco which was good oil.
There is another option during cold weather, the Motor Craft 10w30 Diesel Oil could be used as well. I only used the 15w40 year round but looking back on it I would have had no issues using the Motor Craft 10w30 Diesel Oil during cold months.
I currently have a 2011 Ram 3500 with the 6.7 Cummins, and use the Rotella T6 5w40 year round. My truck is designed to use the 15w40 at temperatures above zero or 5w40 year round. The Rotella T6 5w40 works well with my Cummins.
The bottom line is using the proper oil, quality oil filter and fuel filter changing them as required. The 7.3 has a great reputation. Mine ran great.
There is another option during cold weather, the Motor Craft 10w30 Diesel Oil could be used as well. I only used the 15w40 year round but looking back on it I would have had no issues using the Motor Craft 10w30 Diesel Oil during cold months.
I currently have a 2011 Ram 3500 with the 6.7 Cummins, and use the Rotella T6 5w40 year round. My truck is designed to use the 15w40 at temperatures above zero or 5w40 year round. The Rotella T6 5w40 works well with my Cummins.
The bottom line is using the proper oil, quality oil filter and fuel filter changing them as required. The 7.3 has a great reputation. Mine ran great.
I owned an 02 7.3 for 22 years just sold it for about what I paid for it in 02 only had 92,000 miles when I sold it this year.
Everyone might think iam crazy but I tried a bunch of different oils in it over the years started with dino 15-40s tried 5-40s it didn't like that.
Went to schaeffers 7000 15-40 it did good on that good test results.
Then decided to try the triax 15-40 wow what a difference started real easy in the cold,was quieter it really loved that oil test results came back excellent,didn't burn a drop.
I know everyone talks crap about triax but it really made a difference.
Everyone might think iam crazy but I tried a bunch of different oils in it over the years started with dino 15-40s tried 5-40s it didn't like that.
Went to schaeffers 7000 15-40 it did good on that good test results.
Then decided to try the triax 15-40 wow what a difference started real easy in the cold,was quieter it really loved that oil test results came back excellent,didn't burn a drop.
I know everyone talks crap about triax but it really made a difference.
