2nd gen leaking front axle

[Devils Paw 80]

A friend with a '90 4runner 4x4 says he's discovered a nice puddle of gear oil under driver's side front axle. It's out of town, so I can't inspect. Is there a oil seal that's prone to failure that would be responsible for this, and if so how difficult is the repair? If it makes any difference, this truck had the auto hubs converted to manual. Thanks.

 

[Hiluxonian]

A friend with a '90 4runner 4x4 says he's discovered a nice puddle of gear oil under driver's side front axle. It's out of town, so I can't inspect. Is there a oil seal that's prone to failure that would be responsible for this, and if so how difficult is the repair? If it makes any difference, this truck had the auto hubs converted to manual. Thanks.

Reckon it's the differential seal where the diff joins the propshaft an easy enough fix

Most likely cause, the little pressure valve is blocked or broken on the top of the axle the extra pressure from a hot axle oil expansion etc has forced it to fail... maybe

 

[KLF]

Ya, the first thing to do is figure out if it's the pinion seal, or one of the axles shafts, right behind where it bolts to the CV.

 

[2ndGenToyotaFan]

Yes, check the pressure relief valve on top of the front of the diff. You'll need to pull the front brush gaurd off. Pull the cap off and make sure it's not plugged up with mud or something.