2010 Tundra: diffs and transfer case service

[kevm14]

These go together because the fluid seems like GL-5 75W-90 in everything.

Rear diff fill and drain plug torque is 36 lb-ft

Front diff fill and drain plug torque is 29 lb-ft

Transfer case fill and drain plug torque is 27 lb-ft

Diffs technically take 75W-85 GL-5 but I'm sure 75W-90 is fine.

Front diff holds 2.2 qts.

Rear diff holds 3.8 qts.

Transfer case takes 75W-90 and holds 1.2 qts.

I would need 8 qts of 75W-90 for all of this. Nice and easy. I will make sure to get the kind with LS additive built in and just use it everywhere.

Also need to buy the crush washer kit from Amazon.

Video to reference but some of his torques are wrong and this is very simple work: https://youtu.be/UgqPKS1TEzU?si=pBPb7O5nxblXiBcj

[kevm14]

The front diff actuator is leaking. PO replaced this one preventatively and he gave me the original. The RTV job to the diff actually seems to be holding. The leak seems to be coming from where the motor mates to the actuator housing, so an internal leak. He said he used a Chinesium part AND only replaced it like 2 weeks ago so he barely drove it. My driving was the most it had seen. I'll put the original back on when I service the front diff.

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[kevm14]

Ran out of time/energy so I decided to at least check the level of the front diff fluid. Good thing I did. It was down 0.8 qts. Yikes. I don't think it leaked out - I think he never added fluid after doing the front actuator.

I decided to check the transfer case level and rear diff level. Fluid started dribbling out the fill plugs immediately, thankfully, so they were both good. I probably didn't hurt anything driving around down 0.8 qts in the front diff, since he did this 2 weeks ago, and probably no more than 200-300 miles Only very occasional 4WD use just for testing. So It's probably fine?

I do need to replace the actuator still.

[kevm14]

I'll throw this in here. So one of the codes was C1340 Center Differential Lock Circuit. I think it makes sense to swap back to the original diff actuator before chasing this. It's not clear what the symptom even is because everything seems to work.