Synthetic Oil in Rear Axle

[jok]

Hi all,

Just had my bus into WW Williams for some work including fluid changes in the transmission, rear diff., and fan gearbox. I had them go with synthetic in all. They recommended the following;
Rockwell Diff. 3.58 ratio - Delvac Syn Trans Fluid 50w (mbl 98h193)
Allison HT-755CR - Trans syn Fluid (27101-ctcs)
Fan Gearbox - Delvac Syn GR 75w-90 (mbl 98h98)

Are these the best to use.

Thanks for your input.

John

[luvrbus]

Tough to beat that combination,your wallet is a little lighter huh

good luck

[Tom Y]

I have been wanting to do the same in my rear axle with dropbox. Should I be looking at 50w also? I was thinking 80/90w? Thanks  Tom

[jok]

My wallet definitely is lighter. Had a hard time prying the dollars out of it but figure it is a long term investment.

I was surprised they recommended the 50w for the rear axle, and nervous.

Also had them do a radiator flush and thermostat change with new coolant. Hoping it runs a little cooler.

John

[luvrbus]

Don't be nervous Eaton extends their warranty to 750,000 miles when using Trans 50 about all the off road heavy equipment use it now good stuff

good luck

[jok]

Thanks luvrbus,
That makes me feel better.

Should I think about synthetic for the steer and tag axle oil. If so, what?

Thanks,
John

[luvrbus]

I ran the Trans 50 in my steers and boogies 

good luck

[Utahclaimjumper]

 The downside of synthetics in older machines include finding leaks you didn't know you had.>>>Dan

[wg4t50]

When I did the RTO-910, I had it changed from RT-910 to the RTO-910, new bearings and seals, used only the Synthetic 50, never any issues .

[stevet903]

Here's the link to the recommended lubricants from Eaton -

http://www.eaton.com/ecm/groups/public/@pub/@eaton/@roadranger/documents/content/ct_070589.pdf

They recommend Delvac Synthetic Gear Oil 75W-90 for the rear end.

[Uglydog56]

I have 50w in my rockwell rear and rto-910 trans.

[gus]

Never heard of 50w in diffs, lots of truck and bus transmissions though.

I have to see something credible and written on this before I put 50W in any diff.

That Eaton link doesn't recommend it anywhere!

[bevans6]

Transmission oil is not hypoid gear oil, it does not have the extreme pressure modifiers that allow the sliding action of the gear faces to survive in a hypoid gear differential.  So if your differential is the standard bus type with hypoid gears, you either got sold the wrong oil, or it's a differential oil, not a transmission oil, or you got the name wrong.  50W is far too light for a differential - but transmission oil is rated on the same SAE scale as engine oil - not the different scale for differential oil modified with extreme pressure additives for differentials.

I would find out the answer to the question, and if they did put 50W transmission oil in I'd get it out before I drove the bus.  You can kill a differential very quickly indeed with the wrong oil.

http://en.wikipedia.org/wiki/Gear_oil

Brian

[luvrbus]

Good grief guys the Mobil 50 covers GL-1 to GL-4, and Gus dig a little deeper Eaton does warranty their transmission 750,000 miles using Delvac 50 with 500,000 mile oil changes and in case don't know what GL means that stands for gear lube the Delvac 50 is shipped in Mack and Volvo

Fwiw Cat uses 30w on the gear train of their equipment you think your bus is under a load lol try hauling 37 yards of dirt


good luck

[bevans6]

Clifford, I have no idea why you are talking about Mobil 50 GL, but 98HL93 Delvac ain't a gear lube as far as I can tell.  It's a transmission oil.  If you want to put in in differentials, fine by me.  I wouldn't.  I would put gear oil in a differential.  Like maybe 98HK85 or some other gear lube.

Brian