colter

89 auto trans.

Can you get a rebuilt extension housing that already has a new bushing and seal installed and also been checked out condition wise?

The rear housing on mine had been leaking for a while, but developed a loud squeal recently. I also noticed the driveshaft yoke has play in it as you can wobble it around some. So I plan on removing the extension housing to get that fixed as I figure the housing is worn. Also new ujoints in the driveshaft while that is off.

Thought of taking the extension housing to a transmission shop to get checked out and new bushings, etc. installed. But thought maybe this is something you can buy already done?

I figure the driveshaft yoke will probably have a groove worn in it. Would the yoke need to be replaced, or can a transmission shop fix that by resurfacing it?

confab

1) Probably. I've never bought just the extension housing, but give a quality transmission supply house a call and see. I know most of the used parts I have purchased from WIT Transmission come refurbed with bushings and whatnot already installed.

2) A transmission shop can do that for you very quickly. Doubt it will cost much.

3) Those yolks run pretty hard. My car needs one too and I've been putting it off. Same as yours, grooved up pretty badly.

(Actually, I want to have a complete, steel DS with yolk fabricated for it, as the aluminum where the U-joint caps go is loose.)

I would just replace it with new. If you start taking material off the already worn yolk, it will surely leak.

In fact, you might want to check the joint cap sockets and make sure they aren't wallowed out. If they are (like mine) I'd consider replacing the whole thing. There's drive line and 4x4 shops that do this stuff in house for a not too unreasonable price.

colter

From looking around. Looks like the bushing is the wear item vs. the extension housing also getting worn. So I'm assuming the extension housing is okay. I think I've read there are oversized bushings. Not sure if the bushing would just need to be replaced with a regular bushing or oversized due to wear.

I'll look around for a replacement yoke. Will have to look up the correct size as there seems to be many GM ones so not sure the size that's on the Vette. May get one if it is cheap enough, or wait to see if the yoke in there is grooved. But I'm assuming it probably is and would be best to get a new yoke.

Can the housing be removed with transmission bolted in? I know the exhaust, crossmember, and driveshaft have to come out. Hoping there is enough room to be able to unbolt the extension housing and pop that off without having to mess with rest of transmission.

I was thinking maybe you could get these extension housings that already have been checked and rebuilt. But looks like these housings are Corvette only and so looks best to just take it to a transmission shop to have the bushing/seal replaced.

I can do the ujoints myself with a balljoint C clamp press.

confab

You should, yeah. There's 4 bolts that hold it on, and you'll find a rubber o-ring type seal behind that.

You can drive a bushing back into it without a lot of trouble also.

(Watch them, because many of them are directional. You may see a lube hole in it that you want back in the same place.)

And, yeah.. It's a C-Beam type. So, the extension housing may be corvette only, or corvette and Fbody. I don't really know without looking up part numbers, but it is fairly easy to just re-bush the one you have and it will only cost you few bucks.

The proper way to seat a bushing is with a press, but I use bushing drivers that work just fine. You can probably even use a big socket if you are careful.

confab

Oh, and PS. If your DS has the little dampener wheel on it? Mine did also and the rubber was bad.

Rather than have that thing come loose and be running around under there, I just removed it before it broke.

Others here may differ on this, but I can tell no perceptible difference in vibration, even at speed, with or without it.

colter

I'll take the housing with a new bushing/seal to a transmission shop and let them install that. As I've read of people installing them wrong or something. Figure a trans shop should be able to do it without screwing it up.

I can do the ujoints with a balljoint press as I've done the halfshafts before. Also, read you want to put a jack under the trans as I guess it will tilt down when you pull the crossbeam. Not sure if the differential also needs support.

On the damper. I think you are referring to the round disc thing on the slip yoke at the tranny. Mine is still there. Though I may be replacing that yoke. Still searching to find out the specs of the slip yoke as there appears to be several different types out there.

confab

Supporting the engine/transmission is a good idea. In a lot of vehicles, the engine can lean back far enough to cause damage if you don't.

Break distributor caps. Pinch hoses and wiring. Etc.

confab

This is pretty cheap. Anyone ever deal with these guys?

http://www.contemporarycorvette.com/...haft-automatic

confab

Then there's this. I'm seeing the yolk alone for at or over 100 bucks.

http://www.driveshaftspecialist.com/...tte-Cobra.html

colter

Was looking at checking to see if Denny's Driveshafts knew/have the correct slip yoke. I've gotten ujoints from them before and was looking at getting Spicer driveshaft joints from them.

I may wait until after pulling the housing and then taking the OEM slip yoke to the transmission shop to see if they think it needs to be replaced, or if it can be reused as is. May just need to be wiped down with some emery cloth.

I've also read of people having their driveshaft's balanced after putting in new ujoints and/or slip yoke. May check to see what that costs.

confab

I am glad you posted this thread.

I was just going to order the steel replacement because the ujoint holes in aluminum shaft wallowed out, but now I'm reading about "critical speeds" and angles and everything else.. It is probably just fine.. But, maybe it isn't safe? I'll have to look and measure to be sure.

I had no idea this was such a complicated subject. Driveshafts are obviously an overlooked part of the car that is actually quite involved when you delve into the tech behind creating one that works safely in a high performance car.

colter

From looking around. Looks like a replacement slip yoke without damper for auto is Spicer 2-3-4911X.

Though from reading someone mentioned I believe the above would work, but isn't counter bored. I'm guessing the OEM yoke has a counter bore in it.

But this part number someone posted has a counter bore and may be a more correct replacement yoke without damper: Spicer 2-3-9211X.

VikingTrad3r

when you get the copper bushing pressed out, also put a new oring in. the tailhaft to case oring. i did mine myself with a hammer and socket. if any rtv was used on the oring joining surface, clean it off completyly, dont scratch tve aluminum, i used a popsicle stick. i used hylomar as a coating for the oring.

c beam removal is a pita, a rubber mallet and/or a 5 inch 2x4 with mini sledge is a big hellp. obviously do hit direct with sledge.

use copius amounts of run of the mill bathroom white silicone between the cbeam and the mounting faces when reinstalling. this will avoid it creaking.

while you are there, u should inspect the 10$ rear diff seal. takes 2 min to pull and replace. if its really dirty make sure no grit contaminates any mating surfaces.

what else......the copper is designed to wear before the yoke so id be surprised to see it worn out.



line the shats when reinstalling.

take dizz cap off or u will crush it

plock support the trans dont let the engine mounts twist.


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colter

I'll have to look at rear differential seal. That area is dry. But I'll look around to see how hard that is to replace. I know sometimes on those type of seals you don't have a leak, but replace it while you're there, then get a leak.

I know of the housing oring. I'll also do the VSS oring as that will have to come off. Though I did already replace that oring. I remember that VSS being a pain in the butt getting it to go in.

Will look around for lube to use on crossbeam. I believe GM used something.

I'll make sure to pull distributor cap. Didn't think of it, but safe thing to do.

I'll have a transmission shop replace the bushing/seal since they probably do that all the time and I haven't before.

"line the shats when reinstalling."

I didn't understand what this meant?

VikingTrad3r

i dropped my 6 in the lake this summer and im using my old 4s. the screen is so much smaller my typing accuracy had gone to the pits!

it was supposed to say lube the shaft when you reinstall. just a light finger wipreof atf. basically taking every precaution so the seal isnt damaged on re-insertion.

cheers

colter

Yes, I'll lube the yoke with transmission fluid on install. I have read some say it may tear seal and get a leak if you install it dry.

It's been a couple of years, so I'll go ahead and change transmission filter and gasket. May fill with Dexron 6 as I've got Dex/Merc in there now.

Last time I used AC/Delco filter with aftermarket rubber gasket. The rubber gasket was so no gasket mess to clean up compared to paper type gasket.

colter

I was planning on jacking the rear end up with the 2 jack stands I have. Is that enough room to drop the cross beam and pull it out through the rear of the car?

Or is this something that you need all 4 corners up in the air on jack stands?

VikingTrad3r

jacking only the rear is fine if its really high.

personally id invest in a couple more so you have a bit more reduncy i one fails. you will be under the car for a long time pushing shoving and rubber malletting with the cbeam.

note that you will need something to support the trans. do not let it hange down as it will torque the engine mounts. dont forget the dizzy cap removal.

i ised wood blocks under thw trans pan. i used the jack to adjust the height of the trans for reinstalation. i had all four wheels on ramps, and then 4 jack stands in addition.

colter

It probably would be a good idea to have two extra redundant jack stands placed under the car just encase something happens and the car moves. I've always just used one or two depending if I just needed to have one corner or two corners up in the air. and wheel chokes on the other two points.

Did think of getting drive on ramps.

Yeah I was thinking of getting a 4X4 and a 2X4 to stack up under the trans pan. Maybe also a 1X4 so it would be easier stacking them to get them to fit snugly without having to do so much cutting to get them thick/thin enough to fit snugly.

I may wait to do it this spring. As I'll have to gather the parts and do research on how to do the job as I always find out "Make sure you do this" type stuff from searching around. And I figure by the time I'd get ready to do it, that it would be close to the start of winter.

VikingTrad3r

for clarity, i jack the car up and put it on the ramps. i do not have low profile ramps.