Jump to content

rear diff


Recommended Posts

Big clunk as you take up drive? it will be the driving members on the ends of the halfshafts are slack around the splines.

I put new hubs on and they went slack again in about a month, i think the cure would be new shafts and some HD flanges (these work out cheaper than a pair of genuine ones)

Will.

Link to comment
Share on other sites

it is adjustable but its not easy most of the time you have to move the crown wheel a little closer to the pinion using shims .the only problemis pulling the bearings off [after you got the diff out of the housimg using a spreader] puttig the bearings back on and checking backlash again if not right start again.research it and do it you will be proud of yourself good luck

Link to comment
Share on other sites

  • 2 weeks later...
Big clunk as you take up drive? it will be the driving members on the ends of the halfshafts are slack around the splines.

Well, yes, big clunk! I just bought a truck, which has the clunk every time you switch gears, unless you're really careful.

I removed the propellor, and the flange that sits on the drive pinion. The pinion just dropped inside the casing - you can wobble it with two fingers, half inch, up-and-down. I haven't opened the whole thing, but it seems that the pinion bearings are gone.

I have no idea how the poor thing could even drive as it did. I would imagine that broken bearings would produce a lot of crushed metal that would inevitably jam the pinion/crownwheel and get the whole thing stuck. But it didn't happen.

I am wondering if the pinion & the crownwheel will have to be replaced now?

Another silly question: can you pull the diff from the casing while it's on the truck? It looks like it could be possible to remove the cover from the diff's back, pull the shafts from the hubs and take the diff out.

/Jaroslav

Link to comment
Share on other sites

Well, yes, big clunk! I just bought a truck, which has the clunk every time you switch gears, unless you're really careful.

I removed the propellor, and the flange that sits on the drive pinion. The pinion just dropped inside the casing - you can wobble it with two fingers, half inch, up-and-down. I haven't opened the whole thing, but it seems that the pinion bearings are gone.

I have no idea how the poor thing could even drive as it did. I would imagine that broken bearings would produce a lot of crushed metal that would inevitably jam the pinion/crownwheel and get the whole thing stuck. But it didn't happen.

I am wondering if the pinion & the crownwheel will have to be replaced now?

Another silly question: can you pull the diff from the casing while it's on the truck? It looks like it could be possible to remove the cover from the diff's back, pull the shafts from the hubs and take the diff out.

/Jaroslav

If you have removed the drive flange from the pinion, taken the big nut off the pinion will move as that has removed the preload from the bearings.

You may be able to get the diff carrier out when you have removed the rear cover but you will need a housing spreader to put it back in correctly.

Link to comment
Share on other sites

Well, if it just moved along the axis of the pinion I would agree with you, but it moves sideways. You can rock the external part of the pinion up and down and it seems like what holds the pinion in place is the crownwheel's teeth. Is this normal?

I would expect it to be held in place by the bearings and the only movement allowed should be lateral along the pinion axis.

Link to comment
Share on other sites

There are two bearings either end of the pinion. With the drive flange nut removed I wouldn't expect the pinion to move forwards and backwards more than a very small amount as the tooth contact is at an angle and would prevent this to some degree. If the inner pinion bearing was badly worn, then it's likely that the tooth contact will be lost as the wear increases. To check for excessive play in the differential assembly - remove the drive shafts and check for backlash. Removing the drive flange is not the way to do it as by doing so you are putting more slack in the diff assembly. Rebuilding a Salisbury diff is very time consuming and awkward, as (unless you get lucky), you may have to fit it and take it apart a few times. Setting the correct contact patch between the pinion and crownwheel involves shimming the pinion (to move it either forwards or backwards), and shimming the crownwheel assembly (to move it left or right). The last time I rebuilt a Salisbury axle - I had to to take it apart 5-times before it was correct :(

I would suggest you put the drive flange back on, torque it correctly, remove the driveshafts and then turn the drive flange by hand. A worn bearing will be detectable in much the same way as a wheel bearing will - roughness on rotation and excessive play.

Failing that ^^, just rebuild the diff with new bearings and a box of various shims. Expect to be at it all weekend though :P

Les.

Link to comment
Share on other sites

There are two bearings either end of the pinion. With the drive flange nut removed I wouldn't expect the pinion to move forwards and backwards more than a very small amount as the tooth contact is at an angle and would prevent this to some degree. If the inner pinion bearing was badly worn, then it's likely that the tooth contact will be lost as the wear increases.

Well, I don't remember if my pinion moves back and forth. It wobbles in the opening - that's for sure. I suspect I should be ordering the pinion and crownwheel in addition to the pinion bearings.

Link to comment
Share on other sites

Guest diesel_jim
Have just replaced both half shafts & drive flanges on my rear Salisbury . Can anyone tell me where I

can get a schematic of the diff. , exploded type preferably . Would like to see how it is put together ,

without taking it apart .

Thus:

post-130-1220692340_thumb.jpg

post-130-1220692355_thumb.jpg

it is adjustable but its not easy most of the time you have to move the crown wheel a little closer to the pinion using shims .the only problemis pulling the bearings off [after you got the diff out of the housimg using a spreader] puttig the bearings back on and checking backlash again if not right start again.research it and do it you will be proud of yourself good luck

Using the shims #11....

post-130-1220692412_thumb.jpg

Link to comment
Share on other sites

Big clunk as you take up drive? it will be the driving members on the ends of the halfshafts are slack around the splines.

I put new hubs on and they went slack again in about a month, i think the cure would be new shafts and some HD flanges (these work out cheaper than a pair of genuine ones)

I didn't get it: you replaced the hubs and the slack was gone? And then it reappeared after a month? Where, in the hubs again?

I did check the splines at the hubs (just removed the rubber cups). It seems that the splines there are tight. I did notice however, that one of the halfshafts moves freely along its axis, probably a 1/4 inch, while the other is not. Is it normal?

Link to comment
Share on other sites

There are two bearings either end of the pinion. With the drive flange nut removed I wouldn't expect the pinion to move forwards and backwards more than a very small amount as the tooth contact is at an angle and would prevent this to some degree. If the inner pinion bearing was badly worn, then it's likely that the tooth contact will be lost as the wear increases. To check for excessive play in the differential assembly - remove the drive shafts and check for backlash. Removing the drive flange is not the way to do it as by doing so you are putting more slack in the diff assembly. Rebuilding a Salisbury diff is very time consuming and awkward, as (unless you get lucky), you may have to fit it and take it apart a few times. Setting the correct contact patch between the pinion and crownwheel involves shimming the pinion (to move it either forwards or backwards), and shimming the crownwheel assembly (to move it left or right). The last time I rebuilt a Salisbury axle - I had to to take it apart 5-times before it was correct :(

I would suggest you put the drive flange back on, torque it correctly, remove the driveshafts and then turn the drive flange by hand. A worn bearing will be detectable in much the same way as a wheel bearing will - roughness on rotation and excessive play.

Failing that ^^, just rebuild the diff with new bearings and a box of various shims. Expect to be at it all weekend though :P

Les.

Previously, I claimed that the pinion bearings are gone, but after reviewing the pictures and rereading the workshop manual's section that describes the axle rebuilding procedure, it occurs to me that what I observed (loose pinion) was expected because after you remove the flange, the outer bearing cone falls out. So, maybe the pinion bearings are fine after all.

Now, your response makes a lot of sense. Will do the test you're describing tomorrow. I hope the clunking noise is caused by the halfshaft splines on the inner side (the hub sides seemed to be OK). Since I just bought the truck, I'd like to run a complete set of maintenance first: replace fluids, grease whatever needed, timing belt etc. This is not the right time for dicking around with such a serious job as diff rebuilding.

BTW, why do you have to spread the axle? What's the point? Is it done to remove slack?

Link to comment
Share on other sites

I would suggest you put the drive flange back on, torque it correctly...

The book says that the correct torque is set by tightening the nut and checking "drive pinion resistance to rotation", which means I'd have to open the diff to be able to set it correctly. I'm screwed!

Link to comment
Share on other sites

Yes, but you are only putting it back together in it's original (worn?) condition in order to determine the problem you have. Once reassembled, remove the driveshafts, check the ends for a step in the splines. Rotae the drive flange gently in either direction and feel for any play between the pinion and crownwheel. Pulling down hard on the flange while turning it will tell you if the bearings are worn (you will feel any roughness).

Les.

Link to comment
Share on other sites

Rotae the drive flange gently in either direction and feel for any play between the pinion and crownwheel. Pulling down hard on the flange while turning it will tell you if the bearings are worn (you will feel any roughness).

And so I did, although I forgot to pull down hard on the flange (damn!). Rotating the flange was smooth and I could feel no roughness. However, I think there is a point (points) where something drops inside the diff with a little knock. Maybe it's a satellite pinion wheel sliding on the cross-shaft?

The wheel flanges and shafts need to be replaced as there is a significant free play. Even if there is a problem in the diff itself, I won't know it for sure until I replace the half-shafts and the flanges.

BTW, there was a small amount of oil coming from the wheel flanges when I was removing them. Is it normal? I put some grease on the shaft ends, but now I think I shouldn't have done this. Well, it depends on how the half shafts are lubricated. Does the gear oil come all the way along the shaft to the wheel flange or, perhaps, it's contained inside the central diff enclosure?

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...

Important Information

We use cookies to ensure you get the best experience. By using our website you agree to our Cookie Policy