The Stovebolt Site Forums The Parking Lot Big Bolts 1946 2 ton COE Pinion Seal

Good Day Gentlemen. My 46 2 ton has a leaking pinion seal. Is that able to be replaced from the outside? Driveline, yoke, meausre nut position? It appears so, but I wanted to make sure before I pull it apart.

A leaky pinion seal can be a symptom of worn pinion bearings. A new seal won't last long if that is the case. Can you feel any play in the pinion shaft when you try to move the yoke up and down or fore and aft?

Tom - I looked at your Gallery Page and it doesn't list if your COE truck has a single or 2 speed rear axle??? More accurate details can be provided if we know which axle you have.

As your topic is specific to "Big Bolt" trucks, I've moved the thread over to the Big Bolts forum for further help and conversation.

Didn't think of that sorry. This particular one is a single speed rear. I don't feel any play in it but I will give it a thorough checking prior to pulling it.

thank you!

Zero play, thank goodness. I'll check it again without the driveline, but it seems solid as a rock.

On my 59 I was able to pull the whole pinion assembly from the axle to change the seal out. It was just as well, as the driveshaft yoke required a ton of persuasion with a torch and a hammer before it came off.

Tom - Here's a 1-1/2 & 2 Ton diagram from the 1947 Truck Shop Manual (same diagram as shown in the 1942-46 manual but only listed as 1-1/2 ton in that book) showing the single speed axle cross section view. Hope this will help you see what is where and it does look like you can replace the seal like you want, although yours might be as stubborn as Puffie40's. Hoping not!

Thank you, I will probably take the entire assembly the the bench and that is great advice. They all look easy until we remember they aren't.

And, thank you for the diagram! That is very helpful. Looks like I can get in there from the front.

Your success in removing the pinion might depend on how tightly the double-race ball bearing is gripped by the housing. Mine was a semi-tight fit, so it didn't take much effort than some gentle tapping with a hammer to move it. Just be on the lookout for shims as that will set the backlash.

The rear bearing on the pinion is a flat roller bearing, so the inner race will slide in and out of it with ease.

Good to know thank you. Have you ever tried a puller of some sort? I was contemplating the possibility.

Looks like my old T-150 two speed in that, once you get the U joint flange pulled out, you can just remove that front cover to do the seal, and it shouldn't have any effect on the rest of the innards. Just make sure you put it back how it came out in terms of any shims.

I did use a split-plate-style bearing puller on the components about halfway through pulling the yoke. It did make pulling the rest of the parts off a lot easier so I could wash everything. I was then able to use a hydraulic press at work to push the bearings back on.

Since i had so much trouble getting the yoke off, I touched the splines with a wire brush and some needle files until I could slip it on, and slathered the spline with grease before I bolted it back on.

Thank you!

Tom - Do you already have the replacement seal and felt packing, or could you use some help tracking one down???