Pinion seal and front drum seals

[67ChevyPickupMan]

I have some questions. The first one is, is what size is the pinion seal on an original 1967 12 bolt rear non-posi, and how do I remove it with out messing up the backlash on the gears? My next question is what size are the seals on the front with drum brakes. This is on a 1967 2wd C10.

Thanks to those who reply

[69GMC2004]

Originally Posted by 67ChevyPickupMan

I have some questions. The first one is, is what size is the pinion seal on an original 1967 12 bolt rear non-posi, and how do I remove it with out messing up the backlash on the gears? My next question is what size are the seals on the front with drum brakes. This is on a 1967 2wd C10.

Thanks to those who reply

I don't know the size, but if you're just changing the pinion seal for a leak, simply remove the pinion nut and yoke, pop the old seal out, new one in, reinstalled yoke and nut. Just tighten nut enough to keep it from coming loose, too much and you could increase your pinion preload. No need to open up the differential and backlash won't change.

You should be able to look up the seals on RockAuto, if you click on the info button they sometimes have dimensions of the parts.

[BigBird05]

A good way to remove the seal is to punch a small hole in it and use a screw. The screw will work the seal right out.

[Pro299]

If it's only the pinion seal, I usually scribe the nut and yoke, or use a marker, paint pen, whatever before loosening. Change the seal. Then I put the yoke back on and just tighten the nut to line up the marks so the nut is in the same position it was before.

[Accelo]

Pro299 nailed the procedure.
I use a Dremel tool or grinder to add a line on the pinion and nut. Take a picture of the thread. Sometimes you can be one turn off, and still have the marks line up, as the pinion flange sometimes goes on tight.
I use a puller to remove the flange. You can beat on the back of the flange with a hammer but you take a chance of brinelling the bearings. Having a tool to keep the flange from turning while reinstalling the nut is usually the most difficult part of this job. Some use a large pipe wrench. Amazon also sells one for as little as $23.00.
Rick

[truck-kid]

X2 on what Pro99 and Acello said. To add to that you can measure from nut to end of pinion with a scale to get close then continue to align exactly your engraved marks. Resist the urge to go "a little more..." I Also add clean everything well and put some silicone sealer to about the last !/4" of splines inside of yoke on nut side to prevent leaks out the splines and blue loctite on the threads. Dont forget to lube the lip of seal and the yoke seal surface as rust quickly forms on the outer exposed clean seal area of the yoke.

[slikside]

Subscribed. Good info. Need to do this as well.

[gmc684x4]

You can make make a pinion yolk tool look at Chilton manual for torque specs

Use a new nut lock tite it torque to spec check bearing drag with inch lbs beam style torque wrench it will be a 1/4 for low inch lbs
It should be something like 19 inch lbs drag rotating your pinion when done double check that number in Chilton manual

You have to tighten it fairly hard to overcrush the crush sleeve
Intial crushing the crush sleeve many guys use a pipe extension to get enough leverage to crush it

https://www.speedwaymotors.com/Adjus...yABEgLliPD_BwE

[67C10Step]

I just did this on my 67 about a month ago and followed the exact procedure laid out here. I made three, unique markings to make certain I got the nut lined back up correctly. The old seal came out more in pieces but I got it. Started with a normal seal puller and ended up using a small punch to deform it enough to get a small, flat screwdriver behind it and pop it out.