[SIKGMC]

I have a 2009 LMM DRW and I am changing all the fluids to Amsiol. My buddy says I need 10W40 in the transfer case. I say Torq Drive. Is 10W40 good or better?

 

[carkey351]

10w40 is an engine oil and formulated as such. Plus if you are in a colder environment it will be way too thick in the winter (regardless of it being synthetic).

those transfer cases come from the factory with ATF so i'd use something similar. if you are worried about performance then drain it and refill on a regular basis. Torqdrive should be fine to put in there. If it were my truck, especially one that new I wouldn't put 10w40 in it...

 

[skleppy]

If its still in warranty, stick with ATF. If its not, many on the forums here have switched to 5w30 synthetic in the T-case including myself. I haven't seen any reported failures attributed to 5W30 but I haven't really looked either. I change mine once a year and it goes in as clean oil and it comes out nearly as clean. With ATF, I didn't really see a color change. Hard to tell if something is on its way out if you can't indicate something in the fluid. That said though, 10W40 is way to thick to go in the Tcase. If you're doing that you might as well throw some gear oil in there.

 

[flagstaff]

What reason did your buddy give for using motor oil in a tranfer case?

 

[skleppy]

Search it out on the forum here...thats where I came across it. The debate was over whether it would help or prevent pump rub. I can't remeber the specifics of it but it came down to that and ATF being like a hydraulic oil rather than a lubricant which normal oil is.

 

[div4gold]

I believe that the 5-30 synthetic motor oil has a higher flash point than atf.

 

[newdude]

I have a 2009 LMM DRW and I am changing all the fluids to Amsiol. My buddy says I need 10W40 in the transfer case. I say Torq Drive. Is 10W40 good or better?

Neither. Dexron 6 is all you need. Its what is in there from the factory on 07 and up trucks.

 

[k9duramax]

I personally am running 5-30 (40 would be too thick) myself but my truck is an 05. I haven't had any issues and it appears to be quieter engaging and while running in 4 wheel drive. I would go with the TDrive if you want to sway from what is recommended by GM, but FYI even Amsoil recommends their low viscosity trans fluid-

 

[RanaExcavating]

I have been running 5w30 Amsoil in my t-case since 35,000 177,000 now and no pump rub or any issues at all.

 

[SIKGMC]

I searched and found many discussions about 5w30 but nothing about 10w40. I decided to put Torquedrive in it so all my fluids are Amsoil now.