Pinion Shaft Oil Seal

idiocrates · Post by **idiocrates** » Sat May 23, 2009 11:20 pm

Regarding an M38A-1......

I noticed when I detached my rear axle from my frame and it rolled into a position with its input yoke pointing downward that gear oil gushed out from behind the dust shield. My question is.......is it possible to just replace the oil seal without having to go through the whole pinion setup process? Thanks.

Jim

Post by **wesk** » Sun May 24, 2009 11:15 am

Yes. Remove the nut and washer. Remove the yoke. Then remove the seal and gasket. There are special yoke pullers and seal pullers so you can spend bucks for them or just improvise. Clean it all up. Inspect the yoke outer smooth surface for a measurable groove where the seal rides on it. If this is grooved enough to measure a difference in diameter of the yoke's shaft then you must solve this issue before re-assembly. They make redi-sleeves that return the yoke to a straight smooth surface. There are also double lip seals out there and new yokes. When you re-assemble be sure to put a very coat of RTV on the splines. Torque nut to 200 to 220 foot pounds. You'll need a fabricated bar that will bolt to the yokes U'joint bolt holes to hold it still. Some folks use a huge crescent wrench.

idiocrates · Post by **idiocrates** » Sun May 24, 2009 3:49 pm

Thanks, Mr. Knettles. Is it only if I go the route of re-using the existing end yoke that this holds true.....or does it apply to the use of a new yoke as well? I'm not real swift on differentials and pinion gears so I have to be real careful not to bite off more then I can chew here. How much trouble can I get into if the pinion backlash and end play get messed up? Does it just get noisy or does it get destroyed? I've read the Universal Manual and its clearly evident I don;t have the necessary gauges and tools to know if its right or wrong......so if I change the yoke can I be sure nothing else is effected?

Jim