clunking noise sounds like the rear end. Video

Buddy of mine has an 06 cclb 48re truck, it pops when you switch directions, but once switched no problems. His only has 30,000 miles also.
 
whats the noise sound like wile driveing? did this noise just start?
 
sounds and looks like a good amount of backlash between the pinion and ring gear in the rear but i could be wrong.
 
the noise has been happening for a while now, and seems to be getting more noticable. I was thinking it was just noise from my traction bars but I made sure they are tight and now I don't know. The U joints are good, they have been replaced and I checked them. I might pull the cover and see what it loooks like, I just serviced the diffs about 3 months ago so I don't know.
 
D Twigg said:
sounds and looks like a good amount of backlash between the pinion and ring gear in the rear but i could be wrong.
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X2. I've seen older rear ends that move quite a bit more than that and they never had any problems. You probably won't find anything by pulling the cover and looking. You'll need a magnetic base dial indicator to measure backlash, which is probably out of spec from wear. $.02
 
well I might have to have you help me, I'll check and see about a dial indicator.
 
take a dial indicator and measure how much the pinion moves befoe it contacts the ring-gear. it should only be like one thousandths of an inch or so i do believe.
 
cumminsX said:
the noise has been happening for a while now, and seems to be getting more noticable. I was thinking it was just noise from my traction bars but I made sure they are tight and now I don't know. The U joints are good, they have been replaced and I checked them. I might pull the cover and see what it loooks like, I just serviced the diffs about 3 months ago so I don't know.
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what did you do in the servicing? pinion seal?
 
Its pretty simple.. With the truck jacked up pull the cover and mount your dial indicator base on the flat part of the diff where the cover would go. line the indicator up where it will contact the face of one of the ring gear teeth, then rotate the ring gear either up or down untill it makes full contact with the pinion. Zero out the dial indicator, then rotate the ring gear the opposite direction untill contacting the pion gear. Note the reading on the dial indicator, this is your back lash. should be between .005-.008.
 
i think this is my problem too.. Does anyone know if they rent those tools at like Oreilly's or anyplace?
 
grncummins said:
Just torque the yoke to pinion nut a little at a time until the play goes away
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All that does is increase the pinion bearing pre-load..... which is almost certainly not his problem. And in truth is probably just smashing the crush sleeve until the pinion bearing pre-load is so damned high that it honestly feels tight to you again. Not because the BL is corrected, but because the bearings are so bound up that you don't feel any loose play anymore.

On a side note: That is an exceptional plan for really extending pinion bearing life.



To the OP, first of all, the truck/differential is probably fine, and will drive perfectly for years just as it sits. If you hooked it to a 15,000lb trailer every day for 10 years it would likely be fine...

However....

If things must be Peeeerfect for you, then yank the cover as was already mentioned...

As was mentioned using a magnetic base attach to the flat portion of the housing face where the cover goes. Then placing the dial indicator so that it strokes TANGENT to the ring gear (otherwise the value read is USELESS) do as stated above and while holding the pinion PERFECTLY still gently push the ring gear to the pinion, zero the dial indicator and then gently rotate the ring gear until it stops in the opposite direction. Note the value. Then do it a few times to make sure you have a consistent value. Now you're looking for something in the 5-8 ish range. That's 0.005 to 0.008 inches. Since it will undoubtedly be higher than this, you will have to pull the caps (making sure to KEEP them oriented such that they go back on the same way, same side) and yank the carrier taking care not to lose or mix up the shims if they are outside the bearings as they usually are. Take shims from the end opposite the ring gear and add them to the side closest the ring gear to decrease BL. Also note the preload. If the carrier just falls out in your lap you've got a bearing problem most likely. If it's just loose, then add some shims to snug it back up. Do this on the RG side (usually driver's side) and skip swapping shims from right to left as the additional shims will not only increase the pre-load but will also decrease the BL when added behind the RG.

Now if that seems a bit ridiculous, then just drive the truck like everybody else does and stop worrying about it.

;)
 
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Charles said:
All that does is increase the pinion bearing pre-load..... which is almost certainly not his problem. And in truth is probably just smashing the crush sleeve until the pinion bearing pre-load is so damned high that it honestly feels tight to you again. Not because the BL is corrected, but because the bearings are so bound up that you don't feel any loose play anymore.

On a side note: That is an exceptional plan for really extending pinion bearing life.



To the OP, first of all, the truck/differential is probably fine, and will drive perfectly for years just as it sits. If you hooked it to a 15,000lb trailer every day for 10 years it would likely be fine...

However....

If things must be Peeeerfect for you, then yank the cover as was already mentioned...

As was mentioned using a magnetic base attach to the flat portion of the housing face where the cover goes. Then placing the dial indicator so that it strokes TANGENT to the ring gear (otherwise the value read is USELESS) do as stated above and while holding the pinion PERFECTLY still gently push the ring gear to the pinion, zero the dial indicator and then gently rotate the ring gear until it stops in the opposite direction. Note the value. Then do it a few times to make sure you have a consistent value. Now you're looking for something in the 5-8 ish range. That's 0.005 to 0.008 inches. Since it will undoubtedly be higher than this, you will have to pull the caps (making sure to KEEP them oriented such that they go back on the same way, same side) and yank the carrier taking care not to lose or mix up the shims if they are outside the bearings as they usually are. Take shims from the end opposite the ring gear and add them to the side closest the ring gear to decrease BL. Also note the preload. If the carrier just falls out in your lap you've got a bearing problem most likely. If it's just loose, then add some shims to snug it back up. Do this on the RG side (usually driver's side) and skip swapping shims from right to left as the additional shims will not only increase the pre-load but will also decrease the BL when added behind the RG.

Now if that seems a bit ridiculous, then just drive the truck like everybody else does and stop worrying about it.

;)
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Charles, that is some good info! You answered every question I was just going to ask.. But one question, about how long would this take? Never doing it before but I feel I am pretty mechanically inclined.. It doesn't have to be PERFECT for me, but I have too much play for my likings.. What fluid do you all reccomend putting in the rear end.. I wanted to change the fluid in it anyways as it has never been changed and it has 72k on it.. Thank you!
 
JTProuhet said:
Charles, that is some good info! You answered every question I was just going to ask.. But one question, about how long would this take? Never doing it before but I feel I am pretty mechanically inclined.. It doesn't have to be PERFECT for me, but I have too much play for my likings.. What fluid do you all reccomend putting in the rear end.. I wanted to change the fluid in it anyways as it has never been changed and it has 72k on it.. Thank you!
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I would put back in it what style came out of it. I put synthetic on my new build, but the initial switch is what I think helped cause the initial failure.

It took me about 6 hours to do mine with a new set of clutches in the LSD. That's on a lift and everything within arms reach except the press.

Take it for what it is, but don't fix what's not broken.
 
Scince this came back around I will add that my noise was not the back lash, it was my traction bars poping. I got them tightened up and no more noise. I never did anything with the differential and all is well.
 
good glad ya got it fixed and it was something simple
 
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