HoLLo

iTrader: (17)

So I've been chasing down a driveline vibration, and finally got it narrowed down. Looks like my tailshaft bushing is worn. I was getting some horrible vibes on the highway on decel, and sometimes a little clunk here and there. I got under the car yesterday and found my driveshaft yoke in the transmission has a good bit of up and down play, and side to side play is very minimal. I've had 2 other people very familiar with transmissions also confirm the bushing is bad.

So, now I've ordered a Rockland Standard Gear No Walk T56 tailshaft bushing. I've been doing some reading all over the forums, and while there is some info on these, there's not much thorough detail. I know someone with the bushing tool to make the job easier. Any guides on replacing it, or is it pretty self explanatory when I get the tailhousing off? Any advice from anyone who's replaced one before welcome.

wrd1972

iTrader: (12)

The one I installed lasted a day before breaking loose and spinning in the bore. I caught it before it did damage. Installed a OE one and has gone strong ever since. I seriously doubt you will fix your vibe with that bushing. I have seen them severly worn and be vibe free. Plus the Rockland is stupid overpriced.

calhoon

iTrader: (6)

This is not possible. OE / Tremec does not sell a bushing. It is installed and then finish-bored at the plant. The whole extension assembly is the only OE service part.

Ferocity02

iTrader: (60)

I've done a ton of research on this. There appear to be three options for the bushing. 1, buy a new tail housing with the bushing installed. 2, get the Rockland bushing. Or 3, try a TH350 bushing.

The Rockland bushing is supposed to be a direct replacement, but many have had issues. I emailed them about installing it and here was the response:

Line up the hole in the bushing with the hole in the Bottom (6 o’clock position) [it's actually the 4:30 position] and press the bushing in. If you can coat the outside of the bushing with Loctite green bushing fluid. Try the drive shaft yoke in the bushing and see if it fits and turns freely. If it does nothing else is required. If it is too tight due to variations in the slip yoke, use a drill with a brake hone and some solvent and ream the bushing to fit. 1,000-3,000 will be fine. You should not have to size the extension housing to seat the bushing.

I have one that I will be installing soon. I measured the interference fit at 0.004" which is a lot IMO and it may crush the bushing when installing. I might try turning down the outside of the bushing slightly. Haven't decided what to do yet. You are supposed to punch a little bit of the tail housing into the grooves of the bushing so it doesn't spin.

The TH350 bushing also required some machining to get to fit. You can do a search on here for it.

Ferocity02

iTrader: (60)

I installed mine today. Rockland said they never had to machine the bushing or the tail housing to fit, so I just went with it. I sanded down the ID of the housing and OD of the bushing very slightly to smooth the surfaces, didn't remove much material at all. I then froze the bushing and heated the housing. Pulled the bushing out, coated it with green loctite, and hammered it in. I used a wooden block to get it 3/4 of the way in, then a 1-1/4" socket to do the rest. Then I used a punch to tap some of the housing material into the two notches at the end of the bushing to prevent it from spinning. The housing material seems brittle so I have no idea how well it will hold the bushing. Considering how tight this thing fit I would be extremely surprised if it spun. It was harder to install than the stock one was to remove.

I haven't yet checked the slip yoke fitment. I'm going to pull the driveshaft this week sometime and see how it fits into the bushing. I'll use a brake hone to enlarge the bushing if necessary.

HoLLo

iTrader: (17)

Thanks for the information, I'll remember this when I install mine, which should be sometime within the next week..

What was your purpose of replacing the bushing? Vibrations? I'd like to hear before and after.

Ferocity02

iTrader: (60)

I bought the trans used with 80k miles on it for my Silverado. I was doing the Stage 2 rebuild and replacing worn items. The inside of the bushing was galled up, surface was uneven. I won't be putting in the trans for another couple weeks at least. But I will try to test fit the yoke this week.

wrd1972

iTrader: (12)

Cant speak to that other than to say it is likely OEM spec or close enough to OEM spec to perform the task. In fact, the original bushing i removed looks identical to what is in there now.

All I know is I got a bushing from a tranny shop and they installed and I have had zero tailshaft bushing related issues. I am confident in saying the the original bushing likely was not worn and was needlessly replaced while trying to fix the driveline vibe I had which was really being caused by the 5/6 driven gear in the tranny. I really believe that tailshaft bushings in general are rarely the cause of drive line vibes.

HoLLo

iTrader: (17)

I verified with the local GM dealer, there is no serviceable OEM tailshaft bushing.. But I just received my Rockland bushing today..

wrd, I have read your thread regarding the 5th/6th gear vibrations, but I have checked everything in my driveline, and used 3 different driveshafts, and the most I can find is excessive up and down play where the yoke slides into the transmission. I have concluded a new bushing will at least help it out, if not solve it. It happens in all gears, even neutral, and clutch pressed in.


When I install the bushing, what direction do the 2 small notches point to, towards the trans or driveshaft?? And how exactly am I supposed to "stake" this? I'm not really understanding how. Ferocity, it sounds like you actually knocked some of the housing material into the notches to keep it from rotating???

Ferocity02

iTrader: (60)

I didn't understand the directions either. I used a regular punch, probably 1/8", and smashed some of the housing material into the notches at the end of the bushing. The notches face the driveshaft so you can lock them in place.

Ferocity02

iTrader: (60)

Took a closer look today. Seems like the bushing buckled into the wider of the two grooves very slightly, more so at the front end than the back end. I don't have a bore gauge to verify this though. I'm not sure if this will cause an issue either. I still need to test fit the yoke this week.

Ferocity02

iTrader: (60)

I test fitted the slip yoke yesterday and I was amazing how perfectly it fit. It's a snug fit, little to no play, and spins as smooth as butter. I did not have to hone it out at all.

HoLLo

iTrader: (17)

Great to hear! I'll be tackling mine tomorrow! Hope it solves this bad vibe!

wrd1972

iTrader: (12)

Thats the exact same way mine was and it quickly spun in the bore. If I recall, I had .002" clearance when it failed. I honestly think it needed more clearance for proper operation, like maybe .010" or so.

This bushing does not receive fluid or work on the same premise as a main bearing for example. I would advise to open it up a bit based on my experience.

Ferocity02

iTrader: (60)

I just emailed them about this. They have been very helpful so far. This thing went in so tight I can't imagine it spinning... crazy. Hopefully there will be less stress on it in my truck because I have a 2-piece driveshaft so the slip yoke doesn't slide in and out of the trans with bump, and it's at a constant angle.

Ferocity02

iTrader: (60)

Rockland says to shoot for a minimum clearance of 0.003". Looks like I'll have to remeasure and hone out the bushing a tad.

HoLLo

iTrader: (17)

Can you go into detail a bit on the clearance please? I'm not really understanding the clearance requirement

Ferocity02

iTrader: (60)

OD of slip yoke - ID of bushing after it's pressed in, should be greater than 0.003".

HoLLo

iTrader: (17)

So I finally got around to installing the bushing. When I got everything back together and took it for a drive, I immediately noticed a new noise and vibration. The noise almost sounds like dragging a keychain full of keys on concrete, I don't really know how else to explain it, but imagine that sound. There is a new vibration that kinda mirrors the sound. It's not very loud, but noticeable on the highway, even with the radio on. I'm not really sure what it is. I'm hoping I staked it correctly, as I was kind of confused on how to do it, but it seemed to have a pretty tight fit. Anyone have any pictures of how they staked it?

EDIT: And my speedo needle is a little fluttery under 20mph, I guess I jacked up the sensor or reluctor wheel huh?

Ferocity02

iTrader: (60)

It could be something loose inside the tail housing?

My Rockland bushing seems to be holding up, only have about 100 miles on it though.