1956 Chevy Rear in my 36..I have a pinion seal leak that I was putting off til the winter, but now i have a clunk sound coming from the rear. I checked the gear oil level today and it was not bone dry and a little came out as I pulled the fill screw, but now i have a clunk sounds almost like hitting a piece of wood against metal or concrete.... it first sounded like it was coming from the left rear tire, but with the rear end up and turning by had i think it is coming form the pinion....could I have toasted the ring and pinion?
Make sure it isn't a u joint first before you get into the rear. They can make some bad sounds when worn out. If fluid came out when you removed the fill plug it had plenty of oil.
My old firebird did that. Took rear cover off and the spider gear cross shaft had come loose and actually egged the hole inside the carrier, doubled the size of the hole. Lucky it didn't come out at, well let's say, "hiway speed" and lock up the rear end. So please check it carefully and don't keep driving it until you know what's wrong. Hate to see anything happen to you
I'm not gonna drive it til I figure this out it seems like there is some play with it in gear moving the driveshaft back and forth but I don't know much is OK or not..
Take a flat screwdriver and stick between your u joints and pry in all possible directions, if they are worn you'll see it.
If Ujoints are okay...take it out of gear, and and rotate the drive shaft back and forth by hand...spec is probably .008 or so as measured on the gear, but if you're getting an 1/8th inch of rotation, you'll be pulling it apart. Now if the backlash seems fine, take a look at the tranny side with it in gear, see what it takes to start locking up in all the gears. If all seems fine, check your tranny mounts, check you spring hangers for worn bushing, etc..as they can cause a slap/thud when worn/shot.
no whine just an intermittent clunk/bang I'll check it again, but when i had it up last night in neutral and it seemed like the driveshaft was able to turn back and forth more the .008 lol 1/8 seems right
The old rear in my Ford had play in the pinion, but never made a peep. The pinion seal leak is a symptom of a loose pinion bearing. With bad u-joints, sometimes you see a rust track coming out of the cups.
If u joints are good and no noise look at differential gears and cross shaft and even suspension parts especially if it shows up shifting from forward and reverse.
no posi, it will spin both tires but usually only one will spin. I had the car up on stands and had it in low, the tires were spinning with no sounds. It seems like it is loudest at 30 -35 mph I thought it was on the drivers side at first but my wife thought is was the pass side...it does not clung when putting it into gear....
with the car in park there is almost no rotation of the driveshaft, however if I grab the rear end yoke i can move it up and down about 1/32 to 1/16 and hear and see it move so I'm guessing bad pinion bearing? it clicks when I move it back and forth...no noise with the car in gear rotating the tires forward or backward
Am I going to have the pull the whole gear Assembly out to replace the bearing or can it be done from the front?
I've changed out several rear ends in my 56 due to messed up spider gears. Do you like doing burnouts when making a right turn? Sent from my iPhone using H.A.M.B.
Pull it apart and look at everything... bite the bullet. Do you have another rear to swap in while you play with the problem child?
no. its going to be off the road until I fix it. I'm mulling over options now I can see if I can get another differential with the same gearing. 3.70 I also see there are posi conversions for these if my ring gear is still good. Or I can have mine rebuilt, I've never done and don't know what the cost will be.
From what I understand the pinion bearing does come apart. I just bought the bearings, shims, crush sleeve and gasket to rebuild a 3.08 and it cost about $100.
After you remove the ring gear and carrier that is only done after you remove the third member or chunk.
Sorry, what I meant by the pinion bearing coming apart is that the pinion bearing does fail and makes the pinion move around. The center chunk I bought has marks on the ring gear from the pinion walking because of a failed pinion bearing.
Fact of the pinion seal leaking and that you can move it up and down both indicate worn or failed pinion bearing. As suggested by several, time to pull the center section and evaluate further. BTW, you should be able to find another center section without too much trouble, might be wrong gear ratio; but for temp driving it will work. All the axle splines are the same and any of the 55-64 center sections will interchange. Of course the used center section may be a gamble as well...... The 55-64 Chevy rearends are not the strongest, but they can handle small block OK. There is a company in TX(?) that makes some helpful parts to strengthen the rearend, or even for parts to fix yours. Those old 409 super stockers need all the rearend strength help they can get.
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