The Stovebolt Site Forums The Shop Area Driveline Broken Axle Shaft

I went over a pretty rough bump and now the truck doesn't move at all. It feels like the gears shift, all the linkage appears to work, and it feels like there is pressure on the clutch pedal. But it seems like the clutch is permanently disengaged.

What do you suppose is wrong? Could it be the clutch, tranny, or diff? I have a poker run I'd like to go on this weekend. Thanks.

engine off, put it in gear (level spot) and move it forward or backwards, if the driveline does not rotate, it is something in the rear end, of it does, then I'd look at tranny or clutch.

with it started and idling, if you try to put it in gear without your foot on the clutch pedal, does it go into gear, or grind a bit?

It sounds like you broke an axle shaft. Try to engage a gear without pushing the clutch in. If it grinds, the clutch is probably OK. Then jack up one rear wheel at a time with the trans in any gear. If one wheel turns with less resistance than the other, that's the side with the broken axle. You can also drop the rear end cover and see which wheel makes the spider gears turn when it's jacked up and rolled forward and back.
Jerry

You guys are awesome, thanks for your help. The right rear wheel seems to spin a bit easier than the rear left. Also, there is a lot of play or wobble in the wheel. It seems very loose.

What is involved with changing an axle shaft? It looks like the differential has to come apart somehow.

Is it common for an axle shaft to break? I was just turning onto a paved road from gravel, and of course the road was terrible.

jack up the rear, remove tire, then brake drum, If 1/2 ton, then remove backing plate and outer part of axle. You should see the broken part of the axle inside the tube. (assuming it broke towards the outer end, mine have in the past) take a piece of wire and tie a loop in the end, you should be able to put that around the axle (pushing it on with a long screwdriver or something) and pull it out.

Some GM axles have C" clips on the inside, and you must remove the center pin out of the spider gears first. I am not sure what you have for a rear in yours.

Here's an update. The differential is 4:11, and the c-clip came out easy after the center pin and spacer block.

The axle was broken right next to the differential, so I used a long magnet pick-up tool to pull it out.

The tough part is tracking down a replacement axle shaft before the weekend. Thanks again for the assistance.

I have two questions.

First, the replacement axle is very slightly pitted from corrosion on the bearing surface. Is this of any concern at all? Will it damage the bearing over time? I cleaned it up with fine sandpaper.

Second, the manual says there should be 0.014" between axle shaft an spacer, but I measured closer to 0.040". Is this important?

I'm just happy that the axle is in and I'll be on the poker run.

.040" sounds like a lot but it would work.
Some times you can turn the block 90 degrees and it will work better.
Chevrolet sold different width blocks to set that axle end-play.

Light rust pitting is not a concern, pitting from the case hardening coming off is.