7.3 Ford powered motor home oil Qs

On the free way I run about 60-65 mph and the engine is below 3k in this scenario, on the the grades, depending on steepness it'll begin kicking down as needed and I use foot english to maintain right around 4000 rpm. Some grades like on interstate 90 these passes will have me down to 3rd or even 2nd gear pulling for some miles. I could easily push the engine well into the high 4ks but I prefer not to.
That sounds good. The torque curve is very flat and there is a slight peak near 4000 rpm.
 
I know this is a contrarian thought but read the book, follow directions. Motorcraft 5W-30 will probably do just fine. I second the idea of taking used oil samples at every oil change. This will show you wear metals and wear trends as well as possible fuel dilution or other contamination. I have 42,000 miles on my V-10, run 5W-30 semi synthetic on a 5,000 mi maximum interval (1 year, usually about 4500 miles) and everything looks good.
 
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If you want the absolute best protection, might be wise to reach out to @High Performance Lubricants and see what Dave recommends, I assume it might be a 5W-40 Euro lube.
Dave maintains that the SuperCar line is their pinnacle of protection for road going cars. There may be HPL oils may last longer or do specific things slightly better, but overall SuperCar is the best choice.
 
2023 ??? Isn't motor still under factory warranty?? if yes, then I would make sure 100% with ford or your local dealer that you wont void warranty by running just any oil in it
 
i will also recommend some HPL lube. any of their 5w-40 is what i would look into. could probably do 10-15k intervals on normal old PCEO 5w-40 to make it economic.
 
Was looking at an oil report on here from a 7.3 Godzilla using Mobil 1 5w40 on repeated runs. I like how his numbers continued to improve. Easy to purchase, 1 gallon jugs so buy 2 and a filter.

F350 UOA.webp
 
Your engine has an oil cooler. With your sensible driving style I doubt anything other than the Ford recommended oil is justified.

As mentioned above your engine will be happy at that RPM range - vs. an engine in a service truck that idles all day (for example).
 
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I know this is a contrarian thought but read the book, follow directions. Motorcraft 5W-30 will probably do just fine. I second the idea of taking used oil samples at every oil change. This will show you wear metals and wear trends as well as possible fuel dilution or other contamination. I have 42,000 miles on my V-10, run 5W-30 semi synthetic on a 5,000 mi maximum interval (1 year, usually about 4500 miles) and everything looks good.
The concern I would have is that any Semi Synthetic is likely 80% conventional oil (Group I, Group II), and only 20% group III synthetic oil.
The OP could still go by the book and still use a 5W-30, but use a Euro 5W-30 oil with HTHS >= 3.5, such as Castrol Euro 5W-30 A3/B4. The added phosphorus and zinc anti-wear additives of that A3/B4 spec would help prevent wear and the HTHS >= 3.5 could really provide protection while climbing the long hills that he mentioned where RPMs and engine temperatures rise.
 
The concern I would have is that any Semi Synthetic is likely 80% conventional oil (Group I, Group II), and only 20% group III synthetic oil.
The OP could still go by the book and still use a 5W-30, but use a Euro 5W-30 oil with HTHS >= 3.5, such as Castrol Euro 5W-30 A3/B4. The added phosphorus and zinc anti-wear additives of that A3/B4 spec would help prevent wear and the HTHS >= 3.5 could really provide protection while climbing the long hills that he mentioned where RPMs and engine temperatures rise.

the V-10 is not a highly sophisticated engine. The consistent use of UOA will show me wear metals and any unexpected changes to contaminants or wear. As long as those things remain low I'm not concerned about a "better" oil. Engine wear is my concern. YMMV.
 
Your engine has an oil cooler. With your sensible driving style I doubt anything other than the Ford recommended oil is justified.

As mentioned above your engine will be happy at that RPM range - vs. an engine in a service truck that idles all day (for example).
As suggested, do a run with the MC 5w30 and sample at say 3000 miles? I have a Fumoto valve to install upon oil change so easy to grab a sample.
 
the V-10 is not a highly sophisticated engine. The consistent use of UOA will show me wear metals and any unexpected changes to contaminants or wear. As long as those things remain low I'm not concerned about a "better" oil. Engine wear is my concern. YMMV.
This one is the 7.3 gasser V8 if that makes a difference.
 
Recently purchased a 2023 32' motor home with a 7.3 Godzilla motor. I've weighed the coach several times, it's about 23,300 lbs fully loaded to travel with both of us in our seats. add the GMC Canyon and we're moving about 28,300 lbs. With that said we're in the pacific NW with many long steep hills, and plenty of mnt passes to travel up and down. I'm saying all this to emphasize that the engine works very hard but I don 't abuse it. I am trying to decide what to use for a motor oil. The manual calls for Motorcraft 5w30 syn blend which I'm fine with, I used it for 150,000 miles in my Ford Escape. My plan is to run the Motorcraft and boost it with Schaeffer's 132 Moly EP and probably stick to 5k runs. Looking for some input and open to suggestions. Thanks
I had the V10 in my MH and it didn't seem to work that hard just higher rpms. I used Mobil 1 5-20 at 4-5k oct's. Never used a drop.
 
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This one is the 7.3 gasser V8 if that makes a difference.
Sorry I missed the 7.3 - it was pretty obvious being it's the thread title! However, my answer doesn't change. Wear and contaminates are the issue. Motorcraft should do just fine. All my gas engines run on Kendall (another Phillips 66 product). The bodies wear out before the engines and I have never had to open up an engine. The list includes a Duramax, a couple of Ford 5.4 V8s, two 5.0 V8s, a 3.0 V6, a 3.8 GM, a 2.8 GM, a 4.0 inline 6 in a Jeep, assorted small block Chevies...you get the picture.
 
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Sure. Any idea how many miles you will put on the RV?
Well I haven't owned it for a year but I'm going to say 5000 miles a year and in a few yrs when traveling some more hopefully 10kper yr.
 
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