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
7.3 Ford powered motor home oil Qs
- Thread starter MMB
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maybe look at a good synthetic 5w-40 Sn/ Sp rated oil , like Ultra 1 plus or, Delo XSP 5w-40- Pennzoil euro oils are decent and if you have access to Schaeffer's or Amsoil, they have excellent engine oils also. 0w-40 may also work as well. I am sure someone will mention Mobil here as it's a fan boy favorite on here. many good brands to choose from. use of additives maybe not a good idea,but use a well formulated oil with proper approvals and licenses and reputation.
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I'd go 15w40, 5w40 if driven in temps under 10°F.
It's port injected and NA, so no LSPI worries; a solid diesel oil will work well.
It's port injected and NA, so no LSPI worries; a solid diesel oil will work well.
Euro 0/5w-40.
Forget trying to play garage chemist.
Forget trying to play garage chemist.
moving 28k lbs will cause anything to downshift and work hard. I would lean 5w-40 and would get oil analysis done for at least the first 30k miles to see what oci works and what doesn't. that's a lot of weight to move day in and day out for a gas motor.
Some of the linked threads here may be of assistance. In any case, the MOFT is your concern. No $30 UOA is going to show whether a 30 or a 40-grade is better.
https://bobistheoilguy.com/forums/t...ome-with-ford-7-3-gas-engine-oil-type.384853/
https://bobistheoilguy.com/forums/t...ome-with-ford-7-3-gas-engine-oil-type.384853/
A euro rated 0/5w-40 if it has to start in low temps where you travel like below 0f and if not use 15w-40. It's what I use instead of 5w-30 in both my pushrods. Delvac extreme 15w-40 is what I'd use if I was pushing that 7.3 gas near its limit. What're your trans temps as well.
If you think you need to dump something other than a fully-formulated motor oil into your sump to make your engine survive, you should just buy a better oil.
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.
Your plan is fine, keep the oil fresh and remember you don't need to be first up the hill. Ford told us when they rebuilt our 7.3l at work to run higher zinc oils. I'd pick at least a 0-15w40 and keep oci to 5k max. Adding the Moly EP to 5w30 will thicken it up, so no worries if that is the route you want. Good luck with it
Higher RPM is actually desired when it comes to MOFT. It’s the low RPM and high load that challenges the MOFT. I would not be afraid of using RPM to my advantage, provided the oil temperature stays under control.
MOFT?
Not sure what you're asking but the driveline is rated for a GCVW 30,000 and I'm typically 15-1700 lbs under that.
I only have the factory trans temp guage which remains in the safe zone. No real numbers like the Autometers give in my F350 auto meter