Zundfolge
Always learning...
Over the course of about a month the van ('06 2500 267K) had developed a droning/gear sound that was present at all speeds and directly related to vehicle speed. I could more or less rule out wheel bearings because for one, it was a very distinctly gear sounding noise, and the sound did not change while turning vs. going straight. At low speeds it was a "wub-wub-wub-wub-wub" like a Jetsons spaceship, and at higher speeds a very loud droning whine.
Thread: https://sprinter-source.com/forum/showthread.php?t=71144
I had initially (and as it turned out erroneously) attributed it to a recent gear oil change I had done with Mobil 1 75W-90 Synthetic LS lube because it seemed to follow shortly thereafter, but what I found inside was definitely not due to the oil type - and there are reportedly many people on here running that stuff with seemingly no ill effect. So at first I changed out the oil again with the Titan 80W-90 from europarts, and in my rush had forgotten to check the state of that drained oil, which would have shown me a lot of metal shavings. 1 month after the fresh fresh lube I drained it again, and it was full of metal. I ordered a differential rebuild kit from europarts ($300) which includes pinion bearings, diff carrier bearings, shims, new pinion seal, gear marking paint, pinion nut, and ring gear bolts <(not needed in my case).
When I pulled the cover I didn't see anything wrong other than the metal in the oil, no visible carnage, so I pulled it all apart. Below I'll document this process in a way that someone could use it as a step by step guide should you need to do this - and I really hope you don't because this job is a bear!
Tools you'll need aside from the basics:
-Shop Press (used a harbor freight 12T)
-Bearing puller
-Seal/race drivers
-Dial indicator w magnetic base holder
-Beam style in. ib. wrench with increments of 1 in. lb. AND adapters to adapt your 1/4" drive wrench to your likely 1/2" drive (but could be 3/4" drive) 32mm 12pt. socket.
-BFH's
-Beer, time, and tenacity
Carefully watch this video:
https://www.youtube.com/watch?v=OurJHaiy6kI&t=17s
Allow at least 2 full days, you may not need them both but in case you do...
1) With the van recently driven for better fluid draining, jack van up off all 4 (but I really just hope you have a lift) and support very well with jackstands and whatever safety redundancies you employ - it's good practice to not rely only on jackstands. Stacked wood blocks, leaving the jack in place (as long as it's not in the way) etc. are all practices I tend to follow.
2) Drain diff - 14mm hex at bottom pass. side of van
3)At this point you'll want to switch to removing the axle half shafts from the diff, as to get the carrier and pinion out the half shafts must be removed. Remove the rear tires, remove brake calipers (two 18 mm hex bolts) and set calipers up on leaf springs. Wire into place so they don't come crashing down.
4)Remove rotor - T50 torx is that rotor retaining bolt. If they don't come off easily use a RUBBER mallet to the back of the rotor.
5) Remove parking brake shoes - this is tricky stuff. Almost the worst part of the job IMO. Start by removing the retaining springs in the middle of each shoe (somewhere around 11 and 5 or so? Maybe 1 and 7 on the other side?) I used a 7/16" socket with a little bit of shop towel pressed into it on the end of a 6" extension. The little piece of shop towel pressed into the socket allows for some grip against the spring to turn it. Line up one of the 3 large access holes in the hub over those springs, and use the socket shop towel extension thing to push the spring (hard), and on the backside you will see the other end of that spring is a hook that goes through a slot, you need to twist that spring so that the hook passes through the slot and releases the parking brake shoe. Do both shoes. Adjust starwheel adjuster all the way closed. Separate shoes enough to remove starwheel adjuster. work magic to remove springs that pull shoes together. I found that a very strong dental pick can be used to pull the spring down from behind enough to release it from the slot in the shoe. Remove the little articulating pivot-majigger from the parking brake cable as it pokes through into hub area by just popping out the pin holding the end of the cable and the pivot-majigger together. Set all parking brake components on a piece of cardboard in the order and orientation they came out!!! And take pictures of it all, you do not want to be guessing at how it all goes back!
IMG_1355 by Nicholas Tavasieff, on Flickr
One of the springs that holds brake shoes onto axle tube end:
IMG_1353 by Nicholas Tavasieff, on Flickr
6) There are now 6 (IIRC) 13mm (IIRC) bolts holding the hub the the axle ends. Poke your socket with extension through those access holes and zip those bolts out. A few zip ties will need to be cut around the axle tube to free the wheel speed sensor enough length to pull the axles out. No need to cut speed sensor wire. The axles should now pull right out, but get creative with mallets and wood blocks if you need to. You only need to pull the axles out about 3 or so inches to clear the splined ends out of the differential carrier. Repeat for the other side (duh).
7) Onto the driveshaft - remove the four 13mm bolts holding the driveshaft to the yoke, set driveshaft end off to the side on some cardboard.
8)The pinion nut now exposed has a deformed lip to keep it from loosening, use a punch/chisel to re-form it for removal. It's a 32mm 12pt. socket. Quick impact wrench oughta do the trick.
9) Remove the differential cover.
What I found:
IMG_1334 by Nicholas Tavasieff, on Flickr
10) The sway bar will be in the way of pulling out the carrier, remove the two links where they attach to the chassis - 19mm bolt and nut. Remove the two long bolts from each side where the sway bar bushing housing attaches into the axle. Don't remove the two shorter bolts directly below the sway bar at those bushings, only the long ones that attach the bushing housing.
11) You'll see four bolts facing you, two each holding the bearing retainers. They absolutely must go back in exactly the same way! I marked mine to make sure. Then remove them.
12) The carrier can now be pulled out. It can be leveraged out with a bar, just take great care to pull it straight out, not at an angle. I rigged a ratchet strap around the carrier to my receiver hitch and gave it a couple of ratchets to free it out. MOST IMPORTANTLY PULL THE CARRIER OUT KEEPING THE SHIMS ON THEIR SIDES. There will be a shim (maybe more than one) on either side of the carrier bearings that MUST go back in exactly as it came out. I pulled mine out, wiped them off, and sharpied which side they go on. If you are not replacing the carrier bearings keep the same races with the same bearings too.
Your carrier may come out easily, I needed to nudge mine just a little, my method:
IMG_1342 by Nicholas Tavasieff, on Flickr
Strap method shown with wheels still on FYI,
13) Remove the pinion - from the driveshaft side replace the old 32mm nut on a few threads to be able to use it to drive the pinion out, or use a solid piece of wood as a beater against the pinion shaft to beat the pinion out. Either have someone on the other side to exert some pressure and catch it or pad the inside of the case very well so no damage is done to the pinion when you bang it out, it's heavy and can chip if it falls into the case.
14) Remove old pinion seal from diff housing, being careful not to scratch the machined surface of the diff housing.
15) Drive the races out from both sides - check that video for details.
16) When you drive the larger race out (closer to inside of diff) there will be a shim behind the race. This shim MUST GO BACK IN THE SAME PLACE WHEN YOU DRIVE THE NEW RACE IN!!! (by now you're probably sensing some kind of pattern here).
***note: it's also possible that the bearing will be shimmed between the pinon gear and the bearing cup, so in theory there could not be a shim there, but mine had one behind the race, and NOT under the pinion shaft bearing.
17) Clean out diff with brake cleaner etc.
18) Press inner bearing off of pinion with shop press and bearing puller.
IMG_1362 by Nicholas Tavasieff, on Flickr
19) Press bearings off of carrier.
This side of the diff is easy to get the bearing puller behind to press off:
IMG_1365 by Nicholas Tavasieff, on Flickr
The other side there is no room for the puller to sit, the ring gear bolts get in the way of the puller sitting behind the bearing cup. Destroy the outer part of the bearing by clipping the cage apart and prying it off, along with all of the bearings of course, and you'll then be able to get the puller to grip the lip at the top of the bearing cup, and press off:
IMG_1370 by Nicholas Tavasieff, on Flickr
20) Inspect pinion gear, ring gear, spider gears, all surfaces etc. for unusual wear before reassembly.
What I found:
IMG_1357 by Nicholas Tavasieff, on Flickr
IMG_1358 by Nicholas Tavasieff, on Flickr
***note: before you get to reassembly, put the 2 pinion races in the freezer for a few hours to shrink them a little, this will help them drive into the diff housing a little easier.
Thread: https://sprinter-source.com/forum/showthread.php?t=71144
I had initially (and as it turned out erroneously) attributed it to a recent gear oil change I had done with Mobil 1 75W-90 Synthetic LS lube because it seemed to follow shortly thereafter, but what I found inside was definitely not due to the oil type - and there are reportedly many people on here running that stuff with seemingly no ill effect. So at first I changed out the oil again with the Titan 80W-90 from europarts, and in my rush had forgotten to check the state of that drained oil, which would have shown me a lot of metal shavings. 1 month after the fresh fresh lube I drained it again, and it was full of metal. I ordered a differential rebuild kit from europarts ($300) which includes pinion bearings, diff carrier bearings, shims, new pinion seal, gear marking paint, pinion nut, and ring gear bolts <(not needed in my case).
When I pulled the cover I didn't see anything wrong other than the metal in the oil, no visible carnage, so I pulled it all apart. Below I'll document this process in a way that someone could use it as a step by step guide should you need to do this - and I really hope you don't because this job is a bear!
Tools you'll need aside from the basics:
-Shop Press (used a harbor freight 12T)
-Bearing puller
-Seal/race drivers
-Dial indicator w magnetic base holder
-Beam style in. ib. wrench with increments of 1 in. lb. AND adapters to adapt your 1/4" drive wrench to your likely 1/2" drive (but could be 3/4" drive) 32mm 12pt. socket.
-BFH's
-Beer, time, and tenacity
Carefully watch this video:
https://www.youtube.com/watch?v=OurJHaiy6kI&t=17s
Allow at least 2 full days, you may not need them both but in case you do...
1) With the van recently driven for better fluid draining, jack van up off all 4 (but I really just hope you have a lift) and support very well with jackstands and whatever safety redundancies you employ - it's good practice to not rely only on jackstands. Stacked wood blocks, leaving the jack in place (as long as it's not in the way) etc. are all practices I tend to follow.
2) Drain diff - 14mm hex at bottom pass. side of van
3)At this point you'll want to switch to removing the axle half shafts from the diff, as to get the carrier and pinion out the half shafts must be removed. Remove the rear tires, remove brake calipers (two 18 mm hex bolts) and set calipers up on leaf springs. Wire into place so they don't come crashing down.
4)Remove rotor - T50 torx is that rotor retaining bolt. If they don't come off easily use a RUBBER mallet to the back of the rotor.
5) Remove parking brake shoes - this is tricky stuff. Almost the worst part of the job IMO. Start by removing the retaining springs in the middle of each shoe (somewhere around 11 and 5 or so? Maybe 1 and 7 on the other side?) I used a 7/16" socket with a little bit of shop towel pressed into it on the end of a 6" extension. The little piece of shop towel pressed into the socket allows for some grip against the spring to turn it. Line up one of the 3 large access holes in the hub over those springs, and use the socket shop towel extension thing to push the spring (hard), and on the backside you will see the other end of that spring is a hook that goes through a slot, you need to twist that spring so that the hook passes through the slot and releases the parking brake shoe. Do both shoes. Adjust starwheel adjuster all the way closed. Separate shoes enough to remove starwheel adjuster. work magic to remove springs that pull shoes together. I found that a very strong dental pick can be used to pull the spring down from behind enough to release it from the slot in the shoe. Remove the little articulating pivot-majigger from the parking brake cable as it pokes through into hub area by just popping out the pin holding the end of the cable and the pivot-majigger together. Set all parking brake components on a piece of cardboard in the order and orientation they came out!!! And take pictures of it all, you do not want to be guessing at how it all goes back!
IMG_1355 by Nicholas Tavasieff, on Flickr
One of the springs that holds brake shoes onto axle tube end:
IMG_1353 by Nicholas Tavasieff, on Flickr
6) There are now 6 (IIRC) 13mm (IIRC) bolts holding the hub the the axle ends. Poke your socket with extension through those access holes and zip those bolts out. A few zip ties will need to be cut around the axle tube to free the wheel speed sensor enough length to pull the axles out. No need to cut speed sensor wire. The axles should now pull right out, but get creative with mallets and wood blocks if you need to. You only need to pull the axles out about 3 or so inches to clear the splined ends out of the differential carrier. Repeat for the other side (duh).
7) Onto the driveshaft - remove the four 13mm bolts holding the driveshaft to the yoke, set driveshaft end off to the side on some cardboard.
8)The pinion nut now exposed has a deformed lip to keep it from loosening, use a punch/chisel to re-form it for removal. It's a 32mm 12pt. socket. Quick impact wrench oughta do the trick.
9) Remove the differential cover.
What I found:
IMG_1334 by Nicholas Tavasieff, on Flickr
10) The sway bar will be in the way of pulling out the carrier, remove the two links where they attach to the chassis - 19mm bolt and nut. Remove the two long bolts from each side where the sway bar bushing housing attaches into the axle. Don't remove the two shorter bolts directly below the sway bar at those bushings, only the long ones that attach the bushing housing.
11) You'll see four bolts facing you, two each holding the bearing retainers. They absolutely must go back in exactly the same way! I marked mine to make sure. Then remove them.
12) The carrier can now be pulled out. It can be leveraged out with a bar, just take great care to pull it straight out, not at an angle. I rigged a ratchet strap around the carrier to my receiver hitch and gave it a couple of ratchets to free it out. MOST IMPORTANTLY PULL THE CARRIER OUT KEEPING THE SHIMS ON THEIR SIDES. There will be a shim (maybe more than one) on either side of the carrier bearings that MUST go back in exactly as it came out. I pulled mine out, wiped them off, and sharpied which side they go on. If you are not replacing the carrier bearings keep the same races with the same bearings too.
Your carrier may come out easily, I needed to nudge mine just a little, my method:
IMG_1342 by Nicholas Tavasieff, on Flickr
Strap method shown with wheels still on FYI,
13) Remove the pinion - from the driveshaft side replace the old 32mm nut on a few threads to be able to use it to drive the pinion out, or use a solid piece of wood as a beater against the pinion shaft to beat the pinion out. Either have someone on the other side to exert some pressure and catch it or pad the inside of the case very well so no damage is done to the pinion when you bang it out, it's heavy and can chip if it falls into the case.
14) Remove old pinion seal from diff housing, being careful not to scratch the machined surface of the diff housing.
15) Drive the races out from both sides - check that video for details.
16) When you drive the larger race out (closer to inside of diff) there will be a shim behind the race. This shim MUST GO BACK IN THE SAME PLACE WHEN YOU DRIVE THE NEW RACE IN!!! (by now you're probably sensing some kind of pattern here).
***note: it's also possible that the bearing will be shimmed between the pinon gear and the bearing cup, so in theory there could not be a shim there, but mine had one behind the race, and NOT under the pinion shaft bearing.
17) Clean out diff with brake cleaner etc.
18) Press inner bearing off of pinion with shop press and bearing puller.
IMG_1362 by Nicholas Tavasieff, on Flickr
19) Press bearings off of carrier.
This side of the diff is easy to get the bearing puller behind to press off:
IMG_1365 by Nicholas Tavasieff, on Flickr
The other side there is no room for the puller to sit, the ring gear bolts get in the way of the puller sitting behind the bearing cup. Destroy the outer part of the bearing by clipping the cage apart and prying it off, along with all of the bearings of course, and you'll then be able to get the puller to grip the lip at the top of the bearing cup, and press off:
IMG_1370 by Nicholas Tavasieff, on Flickr
20) Inspect pinion gear, ring gear, spider gears, all surfaces etc. for unusual wear before reassembly.
What I found:
IMG_1357 by Nicholas Tavasieff, on Flickr
IMG_1358 by Nicholas Tavasieff, on Flickr
***note: before you get to reassembly, put the 2 pinion races in the freezer for a few hours to shrink them a little, this will help them drive into the diff housing a little easier.
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