Which oil for Tru Trac

[badazz81z28]

Folks, what brand and weight of gear oil are you all using? I was going to get max gear, but the instructions state the oil should not have friction modifiers in it. I want to use a synthetic.



Thanks

[Schwartz Performance]

It's recommended to use NON synthetic 80w90 in truetrac diffs.

-Dale

[icemanrd19]

seem i asked dse and they are using 75w90 driven synthetic gear oil. According to true tac though it does state do not use synthetic. So confusing. DSE also used driven break in oil for their rear ends also.

break in oil http://www.summitracing.com/parts/jgr-02330/overview/

Oil they then switch too http://www.summitracing.com/parts/jgr-04230/overview/

[badazz81z28]

My Tru Trac is new, it's instructions say to use synthetic or mineral based as long as it meets gl5 and has low to no friction modifier. In not sure what changed

[icemanrd19]

Mine is about 3 years old.

http://www.moserengineering.com/moser/faq/#answer2

What kind of oil should I use? Can I use synthetic? Do I need friction additive/modifier?
A quality petroleum/mineral based oil works best in the Truetrac units. We do not recommend synthetic oil. Friction additive/modifier is not required.

more saying use reg not synthetic

http://www.eaton.com/ecm/groups/publ.../ct_128302.pdf

[badazz81z28]

Mine is about 3 years old.

http://www.moserengineering.com/moser/faq/#answer2

What kind of oil should I use? Can I use synthetic? Do I need friction additive/modifier?
A quality petroleum/mineral based oil works best in the Truetrac units. We do not recommend synthetic oil. Friction additive/modifier is not required.

more saying use reg not synthetic

http://www.eaton.com/ecm/groups/publ.../ct_128302.pdf

When I get back from Vegas I'll post a pic of the new instructions. Bought my 3rd member from moser last month

[icemanrd19]

im 100% using reg dino oil on mine. Seems like a ton of info on the internet and its the safe bet. Now 80w90 or 85w140?

[icemanrd19]

from eatons website. SOB

Detroit Truetrac®
High quality mineral or synthetic gear lubes are required for use in Detroit Truetrac differentials. Regardless of the lube type, always use a GL5 rated lube with the least amount of friction modifier. Mineral lubes lacking friction modifiers (limited-slip additives) were historically recommended for all Truetrac applications because friction modifiers can slightly reduce the bias ratio (limited-slip aggressiveness) of Truetrac differentials. However, to address the continually increasing power outputs of modern powertrains, many vehicle manufacturers have switched to synthetic lubricants as a counter measure for increased axle temperatures and prolonged service intervals. In general, consult the vehicle owner's manual for the manufacturer's recommendations for lubrication type, weight and fill volume. This will ensure lube compatibility with the seal materials and bearings used in the axle. Eaton Performance technical support is available for any concerns in lube selection.

[badazz81z28]

What does friction modifier do to a diff that doesn't have clutches?

[Schwartz Performance]

Interesting. All the instructions I've ever seen say non synth.
My whole life is a lie..... Lol

[badazz81z28]

Decided to give the Motul moser brand a try since they recommend it. Anyone know how much fluid to use in the DSE 9"? That HD round probably requires more lube.

[Schwartz Performance]

Just fill to the bottom of the filler hole on the third member.

-Dale

[Windycity1]

I have talked to the Eaton guys at SEMA and the Power Tour and they stated no synthetic and posi additive not needed.

[badazz81z28]

I have talked to the Eaton guys at SEMA and the Power Tour and they stated no synthetic and posi additive not needed.

This year sema? They have changed the requirements I guess. The instruction do read like above posted. I ended up buying the Motul 300 Synthetic Lube

[Rod]

most of the common GL-5 stuff is synthetic...I use Brad Penn Classic GL-4 80W90 for the last 5 years with no issues with severe racing and track time..

[nokones]

I was also surprised to see the change in their .pdf installation and operation document a few minutes ago. My read on this the synthetic is recommended to address a problem with increasing axle temps and to prolong the service intervals. I'll probably stay with the Valvoline 80/90w dino oil. I have excellent results with the wear factor on gear sets with the Valvoline gear oil and I highly recommend changing the fluid at the beginning of each year. I don't think there will be any increasing extreme axle temps with just autocrossing. If I was open tracking the car then I would consider maybe using the synthetic.

[Windycity1]

Not this year. Couple of years ago.

[badazz81z28]

So just happens I'm looking at 3rd members again....Now Mosers website says they recommend Lucas Mineral based oil for the Tru Trac versus the MOTUL they have been pushing for years! What gives in the flip flop recommendations? FWIW...I haven't noticed any issued using MOTUL since 2015. I have 3 brand new bottles....Should I use them or give Lucas a try?

[dhutton]

Maybe your noise was caused by the Motul? I only say it because you say no issues but you have loud gear noise. I don’t use synthetic lube in rear ends. Have had noisy clutches that were cured by the removal of the synthetic lube.

Don

[badazz81z28]

Maybe your noise was caused by the Motul? I only say it because you say no issues but you have loud gear noise. I don’t use synthetic lube in rear ends. Have had noisy clutches that were cured by the removal of the synthetic lube.

Don

This is what I was seeing in my rear

https://m.youtube.com/watch?v=3XBhMpz1M7s