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Topic: Gear Lube... Which one for a diff? (Read 1921 times) previous topic - next topic
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Gear Lube... Which one for a diff?

I am approaching 250,000 miles on my '02 intrigue.
Time to change the gear lube in the differential per Meritor spec.

Meritor recommends GL-5 SAE 75W/90  gear lube.

I am interested in going synthetic. QUESTION: Which one?
I am looking at
Royal Purple MAX Synthetic
AMSOIL Severe Gear Synthetic
Lucal 10048 Synthetic
Motul Gear 300 Synthetic
Millers CRX LS Synthetic

I am looking for recommendations.
Has anyone changed their Diff Fluid to synthetic?
^Bernie
2002 Intrigue 11346

Re: Gear Lube... Which one for a diff?

Reply #1 –
The Meritor axle I have is a 21145
it is a 21,000 Lb. axle, but CC de-rated it to 20k.


Can anyone help?

^Bernie
2002 Intrigue 11346

Re: Gear Lube... Which one for a diff?

Reply #2 –
Am a believer in synthetic gear lube - do use the correct grade.
IMHO
Avoid purple, Amsoil is good, big believer in Lucas products, Motul is good, never heard of the last one.  Suggest doing it warm, it’s a mess and that diff holds about 4 gallons.
1998 CC Intrigue

Re: Gear Lube... Which one for a diff?

Reply #3 –
Quote from: BlueCoyote –
Am a believer in synthetic gear lube - do use the correct grade.
IMHO
Avoid purple, Amsoil is good, big believer in Lucas products, Motul is good, never heard of the last one.  Suggest doing it warm, it’s a mess and that diff holds about 4 gallons.
You mean USE THE CORRECT GRADE, yes?

Which have you used?
Between Amsoil/Lucas/Motul, is there really THAT much of a difference?

I am wary of shopping by price, but I am wondering if the differences are really measurable in the results.
^Bernie
2002 Intrigue 11346

Re: Gear Lube... Which one for a diff?

Reply #4 –
I changed mine in my 2007 Allure (meritor RS-21145) to Martin Lubricants SynGard 75W90.  On the recommendation of my chassis guy who rebuilds or changes out "a lot" of drive axles.  Martin Syngard.

Brian
2007 Country Coach Allure 37 Sunset Bay 400ISL

Re: Gear Lube... Which one for a diff?

Reply #5 –
I looked at the SynGuard page:
Martin Syngard Products 

And saw the lSynGard™ GL-5 Limited Slip Gear Oil:
Martin Syngard SynGard™ GL-5 Limited Slip Gear Oil

I suppose it does not matter if mine is not a LS diff...

Brian, when you changed, did you change from perolium ased to synthetic?
Was there any perceptible change in performance or "feel"?

^Bernie
2002 Intrigue 11346

Re: Gear Lube... Which one for a diff?

Reply #6 –
No impact to my "Butt dynomonitor or Butt vibration monitor"  I simply think synthetic in a clean environment (like differential) is warranted - better cold weather and hot weather stability in fluid, IMHO.

Brian
2007 Country Coach Allure 37 Sunset Bay 400ISL