Hemtt oil Detroit 8v92

[Elideclan2]

Hello
I'm looking for what type/viscosity oil Hemtt owners are using in there trucks ( engine and transmission)
I am a new Hemtt owner and I'm in the process of getting materials together to do a complete fluid change

thanks

 

[Shark Bait]

I don't have a HEMTT but do have the 8V92 in an MK48 and a HET and all the research ive done lead me back to straight 40 weight. I use Chevron Delo 100. The two strokes don't like an oil with a CF2 (I think that's wat it is lol) rating.

Dave

 

[tim292stro]

All Detriot 2-strokes demand SAE 40 CF-2 (NEVER multi-weight like nW-n).

Chevron Delo 100 is what I run in my bus with a 6V92, I've heard good things about Shell Rotella T from other DD operators.

Search for Delo 100-40-1 at Costco, or Rotella T40-1 at Tractor Supply..

 

[Castle Bravo]

I've been thinking about switching my HET to Delo 100 SAE40. It seems to drink a lot of the 15W40 that is in it and I understand the lower ash content of the straight 40 will help with that.

 

[tim292stro]

CB, you may be looking at an in-frame when you do your oil-change...

The ash in a non-CF2 oil will eat 2-stroke piston rings very quickly - and especially on a 2-stroke diesel (lean burn engine) that's a bad thing since your intake ports are on the bottom of the cylinder. Eat your rings and you start burning oil - burn enough oil and your engine can start running on the engine oil rather than fuel - then you have an engine you don't control the fuel rate to and that's a bad thing.

This video is not caused by specifically engine oil to my knowledge (looks more like too much starter fluid, but they could have shattered there rings and f'd the engine, or just had a bad seal on the roots blower):
https://www.youtube.com/watch?v=8M1o2rpO_JY


It's also fun to watch the young guys versus the old guy when the DD runs away...

DD 2-Stroke oil should have an ash content of less than 1% (the lower the better), and the single weight means it survives the 2-stroke combustion cycle better since in a 2-stroke the lubrication surfaces don't get that recovery "break" during the exhaust/intake strokes. Your bearings will last longer with single weight - if you're running your engine in the cold, Detroit Diesel allows you to run thinner 30W single weight.

 

[m16ty]

This video is not caused by specifically engine oil to my knowledge (looks more like too much starter fluid, but they could have shattered there rings and f'd the engine, or just had a bad seal on the roots blower):
https://www.youtube.com/watch?v=8M1o2rpO_JY


It's also fun to watch the young guys versus the old guy when the DD runs away...

That vid looks like a classic example of the rack sticking.

 

[tim292stro]

yup, or blower seal failure, or broken rings, or bad turbo seal... Diesels run away a lot, look it up

 

[Castle Bravo]

I guess I don't know whats in my 8V92 - It has what I got it with.

According to the various lubrication orders, the M911, M1070, and HEMTTs all say 15W40 or SAE40, depending on climate. The 15W40 is listed first. The MK48 lube order says SAE30 and I can't find the PLS order. I suspect this is like the motor oil in the Allison transmissions, it somehow makes sense on a massive logistics train.

While I do believe a lot of people, yourself included know a lot more about DD engines than I do, I can't imagine the military has been running 8V92s for 40 years and destroying them left and right by running them on 15W40. I know its the government, but...

I do plan on switching mine to SAE40, though, or maybe I'm just changing the oil if its already got 40 in it now.

 

[tim292stro]

Oh, but they do destroy them left and right - they are cheap and fast to switch out since they have a dedicated motor-pool and logistics system to support them. 53, 71, 92, and 149 Detroit Diesel 2-strokes were used in everything from boats (Coast Guard MLB, Pearl Harbor tour boats), generators, water pumps, constructions equipment, trucks... an in-frame with rings, liners, and bearings doesn't cost them much when bought in thousands of units... Remember they bought thousands of spare engines and parts, and got them built new from Detroit years after they were taken off the road in the US domestic market (except the marine motors which can still be had as new replacements).

Lube orders were exactly as you suspect, "good enough" and what they had on-hand, then specifically what the manufacturer recommends (Allison emphatically begs that people only use their automatic transmission oil in the tranny, not motor oil).

 

[Elideclan2]

Thanks for the great info. I will be getting the proper oil this morning. Should I be using the same oil in the tranny? Or should I use 15-40?
thanks again
greg

 

[dk8019]

Allison despises the use of 15-40w in the 740. The correct fluid is Transynd which is their/Castrols fluid. You'll need to change the fluid and then at the regular interval change it again, and then can go to the long maintenance cycle after that. Our trannies hold 38 quarts and this stuff is around $40 a gallon so be prepared for the pinch.

 

[silverstate55]

All Detriot 2-strokes demand SAE 40 CF-2 (NEVER multi-weight like nW-n).

Chevron Delo 100 is what I run in my bus with a 6V92, I've heard good things about Shell Rotella T from other DD operators.

Search for Delo 100-40-1 at Costco, or Rotella T40-1 at Tractor Supply..

I've used Delo 100 40wt & Rotella T 40wt with excellent results in my DDs.

Thanks for posting up the useful info about proper oil for 2-stroke DDs.

 

[tim292stro]

The HT/MT Allisons call for a TES-295 ATF, a CF-4 ATF in heavy duty applications. DEXRON-3 is what is called for in the Allison books.

Again, motor oil is used by the military because it reduces the logistics burdens, while spare parts and repair labor don't cost DoD much at all, so the reduced life is easy for the Military to digest (think of how many miles most of thee trucks have when they hit GL/GP, how many miles do used commercial trucks have on the lot? 10x? 100X?). IMHO owners will want to follow the guidance the component manufacturers give people who privately own and operate that equipment for best longevity.