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Diff difficulties!!!

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If you are feeling it in the mesh of the gears then something has caused the ring gear to move in a side to side condition or the pinion gear to move in or out.

The shim goes between the pinion gear and the pinion end roller bearing cone. the distance tube goes between the two pinion bearing cones, over the pinion gear shaft. The distance tube is used for the drive shaft end bearing location. It determines the bearings preloads against their respective cups/races. The later diffs use a crush sleeve.

If your descriptions of "Gold-gild paint" and "Brass" are in actuality, aluminum (thinking your comment on it not being steel is based on a magnet check) in the honey-colored oil, from the case. One of the pinion bearing cups/races could have started spinning in the housing. Check the carrier bearings too. Sounds like a teardown is the only way to see what might be the actual culprit.

With a part number of STR520, the 3.545 was a Special Tuning only offering. Nothing standard production.

Failure diagnosis is never an easy task, in any business.

Mike
 
It is a 39 and 11 but its not the same. I had both of them. the 39:10 that came out and the 39:11 I was putting in. Each pinion wouldn't mesh right with the other ring, the rings were about the same size as I recall. I played around with them a while before I got a chance to use a press at my work to get the bearings off and on.
 
Well folks I'm back! For entertainment purpose's and the fact that it is raining virtually continually I decided to tear down the diff.
Mike, in particular, was curious about the brass and with good reason.
When I knocked the pinion shaft out it came with a big chunk of chewed up brass and a lot of smaller piece's. This chunk of brass looks like the remains of the brass brake fitting that bolts via a banjo bolt to the brake cylinder on a BE. There is no way this could have gotten in along side of the distance tube unless it had been put in while the diff was being assembled.
Disgrundled employee?? Strike???
At any rate the diff is probably OK if all of the junk going thru the bearings have'nt damaged them. The binding was probably due to the junk and why the car bogged a speed will still have to be resolved
 
Hey go to a bearing supplier and get those pinion bearings and change them out. They shouldn't cost that much and its cheap insurance. Just press them off and press the new ones on with the shims in the exact same place. Those bearings are preloaded, tapered rollers and if brass got in there that could cause your binding.
 
Good point Kim, I guess new bearings even if they are made in china should have the same specs as original. Might as well fit them plus a new seal.

Kurt.
 
Well, that would certainly explain the "Gold-Guild" paint look.

An interesting story to relate that may explain the fitting in the axle housing. Back in the early 80's one of my race buddies had 3 young boys (2, 4 and about 8 years old). They were a hand full and always into something. One day the mechanic that he had noticed one of the younger boys in the race engine room and when he saw him, he came running out. Well, he went in to take a quick look and didn't see anything obvious. He asked the little boy what he was doing in there and he said "Helping put the bolts in the engine"! Literally. He had been in there putting the 1/4" and 5/16" bolts, nuts and anything that would fit down the spark plug holes, the distributor opening and anywhere a bolt, nut or washer would fit. The mechanic had to take the engine apart and get them all out of the oil pan, the cylinders and every where there was an opening. After that, he always locked the door to the room.

So, that might be how the fitting got into the housing. The previous owner might have had his own little helpers. Little boys will do the darndest things.

Clean everything and replace bearings and check it out. If nothing bad on the ring or pinion gears, you can likely save it.

HTH,
Mike Miller
 
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