Gear Oil Question

[NewMexK5]

This is a dumb question, but I have never asked for a definitive answer from anyone. Each time I go to the autoparts store to buy gear oil I see all the different weights and have never found what I need to specifically put in both my Dana 60 and 14 bolt. I have typically just used 80w/90 in the 14 bolt and haven't messed with the 60.

So... what weight oil should I use in both differentials?

Thanks

 

[Hogback Fabrication]

I've always used 80W90

 

[andyblack]

You need to look that up in a manual because it does matter, I think. Also check to see if it needs to says GL-5. (Most gear oil is GL-5). I think 80W90 is what they both use. If your 14 bolt has a Gov-Loc, make sure to use the special additive.

 

[Hogback Fabrication]

You need to look that up in a manual because it does matter, I think. Also check to see if it needs to says GL-5. (Most gear oil is GL-5). I think 80W90 is what they both use. If your 14 bolt has a Gov-Loc, make sure to use the special additive.

gov-loks don't require any special additive.

 

[NewMexK5]

The front has a Trac-Lok, so I put limited slip additive in it. But that's all done with since I'm swapping out the carrier anyway.

Thanks for the replies.

 

[pauly383]

If its cold most of the time in your climate , or if you hardly use the rig hard you run lighter weight .

If its hot most of time in your climate , or if you use the rig hard often , you would want to run heavier weight .

Me , I run heavy synthetic gear oil in both my locked wheeling axles

 

[bp71k5]

If its hot most of time in your climate

You mean Arizona hot, or just regular hot?

 

[NewMexK5]

It gets close to Arizona hot here, just about 5 degrees shy on a good day.

Heck I just never could find anywhere that said a specific weight for the Dana 60. I've only put about 1000 miles on the Jimmy since 2005.

 

[Stomis]

80/90w in a good diff, 85/140w in something thats on its way out.\


Btw its a good idea to put posi additive in any diff. All it does is add impact and wear protection.

 

[Hossbaby50]

If you use your rig hard offroad a good heavyweight synthetic gear oil with anti-shockload additives is a great idea to help keep parts alive happy. I run Redline Heavyweight (75w-250) Shockproof gear oil in my diffs in my K5 and have for years with no problems. It keeps my Detroit and lockright quite and has kept a 10b lockright with 37's and a few broken axles alive. I will be switching to Amsoil in my buggy build and next time I service the K5's diffs but Amsoil is now selling a Heavyweight shockproof gear oil too.