Transfer case

[LR Pat]

02 Duramax 6.6 4WD Tcase actuators is bad, is this a DIY job, or should I take it to a shop ?

 

[Mike L.]

02 Duramax 6.6 4WD Tcase actuators is bad, is this a DIY job, or should I take it to a shop ?

Simple bolt in from the outside.

 

[JerryL]

Transfer case oil change on a 02 Duramax 6.6 4WD:
Two questions to those of you who've already been down this road:
1. What's the best oil?
2. How much?

 

[Duramax One]

1) GM recommends (and I run) Dexron III Oil (GM P/N 12346143) or equivalent Dex 3 from your preferred name brand
2) 2.0 quarts

Torque the drain plug and fill plug to 15 ft-lbs. If you strip the head of either of the plugs, replace them with aluminum plugs (like they are from the factory) to prevent galvanic action from eroding the magnesium case and/or the plugs. It's a pretty simple procedure. I find it is easier to pump (hand pump or whatever you have access to) the fluid into the transfer case than it is to try to fit a bottle up there to fill it. Dex 3 is not very viscous and is easy to pump.

 

[LBZ]

Or, as has been recommended in the past by a few trans builders, 5w-30 synthetic engine oil and overfill by a 1/2 liter or so. Better cooling and lubrication than dex.

Sent from my D5803 using Tapatalk

 

[LBZ]

Also I'm pretty sure the cases are cast aluminum not magnesium.

Sent from my D5803 using Tapatalk

 

[chevyburnout1]

The LMM and up cases switched to aluminum.

 

[holyshitbatman]

The problem with dex is that it boils off and so it gradually will run lower or at least thats what i read and dont be intimidated by the tcase at all its actually really simple to disassemble and assemble.i used dex after i did the pump rub kit but am probably going to switch.u cant over fill with dex cause it foams.alsp i had read it was 3 quarts if u switch idk if thats right not.

 

[mike diesel]

Also I'm pretty sure the cases are cast aluminum not magnesium.

Sent from my D5803 using Tapatalk

Lb7, lly, lbz are magnesium. But you can buy the updated aluminum case half for it.

 

[Chevy1925]

Or, as has been recommended in the past by a few trans builders, 5w-30 synthetic engine oil and overfill by a 1/2 liter or so. Better cooling and lubrication than dex.

Sent from my D5803 using Tapatalk

Mike says going with 5w-30 syn is best for those that do not get under their truck and check fluid level regularly or change it as they should. Dex 3 is still best to put in, just need to watch it if you have evap issues or run lots of miles

 

[LBZ]

Mike says going with 5w-30 syn is best for those that do not get under their truck and check fluid level regularly or change it as they should. Dex 3 is still best to put in, just need to watch it if you have evap issues or run lots of miles

I believe I remember him saying it was all around better for everyone but that was 7 years ago or so now so maybe not.

 

[Mike L.]

I believe I remember him saying it was all around better for everyone but that was 7 years ago or so now so maybe not.

Won't hurt it. It won't vaporize like ATF.

 

[countrycorey]

What about using syncromesh?


Corey

 

[Mike L.]

What about using syncromesh?


Corey

Works great.

 

[JerryL]

Transfer Case Oil Change

I need to apologize to all those who were good enough to answer my questions on what kind of oil and how much for my '02 Duramax Silverado. I was in a hurry and had to run as soon as I got my answer. I'm sorry for not getting back to y'all and saying thanks.
THANK you ALL!!!