Concerns with going synthetic?

I am about to do a complete fluid and filter change on a newly acquired M939A2 as I don’t know the condition of them. I was reading that there are a higher chance of oil leaks developing if I use Rotella T5 or T6 vs. the T4 bc of the detergents that could clean away any sludge. I also purchased a Baldwin B96 oil filter so I assume I need to add a little extra oil for the higher capacity, or does the military use and account for thst

What is everyone’s thought on this? The truck currently has no leaks. And what is everyone’s preference for axels, transmission and transfer case?
Thank you

Conventional oils have trace chemicals that cause seals to swell and and harden more quickly. Synthetics not so much. Seals last longer with synthetic oils as a result. This mostly applies to nitrile/Buna-N seals which Cat doesn't use. HNBR and Viton seals are highly resistant to affects from any type of oil.

87cr250r said:

Conventional oils have trace chemicals that cause seals to swell and and harden more quickly. Synthetics not so much. Seals last longer with synthetic oils as a result. This mostly applies to nitrile/Buna-N seals which Cat doesn't use. HNBR and Viton seals are highly resistant to affects from any type of oil.

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Hello. Your fight. On my low miles A2 I stay with quality conv. oil and a good filter. I respect Syn oil and use it in several of my cars, but do not see the need here. Slight chance of leaks, and not slight chance of oil burn not worth it to me. Oil sump heater appreciated on my truck instead. Warm conv. 15 w 40 seams better than cold 10w or 15w X syn stuff. best luck!

ericp351 said:

Hello. Your fight. On my low miles A2 I stay with quality conv. oil and a good filter. I respect Syn oil and use it in several of my cars, but do not see the need here. Slight chance of leaks, and not slight chance of oil burn not worth it to me. Oil sump heater appreciated on my truck instead. Warm conv. 15 w 40 seams better than cold 10w or 15w X syn stuff. best luck!

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Post script. I vote name brand 80W or 90 W in axles. Plan on 5 tot Gal lube oil in motor. Low to high safe about 2 qts. Low to High safe on stick. I like to follow the Military lube orders, with quality modern oil and filters. No need to re-invent the wheel.