[MYBAD79]

I'm getting ready to adjust my driveshaft angle this weekend. I recently installed a TKO600 and now it is vibrating so that it almost rattles the dashboard loose.... it doesn't vibrate ahen the trans is in neutral and I rev the engine so I assume it's the driveshaft alignment. There are weights on the shaft and there's a sticker stating that it was balanced ...

The differential is bolted to the frame so it doesn't move.... there's not too much adjustment in the trans mount.... what's the best way to get the angles right ??? Acc to keisler it should all be within 5 degrees....

 

[RTGordon]

Typically an unbalanced driveshaft will show up at a particular vehicle speed... or at least be significantly worse. Are you seeing it at all speeds?

Vibrations are one of the most annoying problems to deal with. If everything is lined up properly, do the obvious and check all the mounting points for the new equipment. It could be as simple as a bolt that wasn't torqued down properly.

 

[MYBAD79]

I believe that the shaft is balanced correctly, should adjusting the driveshaft angle not result in acceptable vibration then I might contact the supplier and ask for the shaft to be balanced....

When I installed the trans I did not pay attention to what the driveshaft angle is, the trans is where it is... I bolted the trans to the rear trans support and that's it....

So.... what's the best approach to line it up with the rear end ??

 

[RTGordon]

PM sent

 

[Strider]

I have done 5 of these swaps and I always push the tranny as high in the tunnel as possible. Right up against the floor and then use a poly mount and shim it so the tranny stays just about up there. The flex in the poly allow it to drop down enough to clear the floor.
I then put a magnetic protractor on the end of the output shaft of the tranny.
I take this angle and then do the rearend.
You can shim it up or down with the front mount. I shim it up so this angle when placing the protactor on the pinion yoke is the same as the angle on the tranny but opposite.
The tranny points down I point the yoke up.
The first one I did had a vibration problem. The next 4 I did the way I just described and no vibrations.
Good luck.
I also do side to side alignment but I won't get into that here

 

[mrvette]

I have done 5 of these swaps and I always push the tranny as high in the tunnel as possible. Right up against the floor and then use a poly mount and shim it so the tranny stays just about up there. The flex in the poly allow it to drop down enough to clear the floor.
I then put a magnetic protractor on the end of the output shaft of the tranny.
I take this angle and then do the rearend.
You can shim it up or down with the front mount. I shim it up so this angle when placing the protactor on the pinion yoke is the same as the angle on the tranny but opposite.
The tranny points down I point the yoke up.
The first one I did had a vibration problem. The next 4 I did the way I just described and no vibrations.
Good luck.
I also do side to side alignment but I won't get into that here

I have no doubt Norval is technically correct as above, engineering wise...makes total sense....but when doing my two tranny swaps.....I made two assumptions...first that the lateral/side-side has to be the same, allmost no matter what tranny, especially since mine were automatics going in place of a muncie....I took the bellhousing and muncie set up/bolted together face down on the kitchen floor (I was not married then) and took my framing square and a tape, made some lines and calculated the rear mount height as a function off engine block locating pins....did the same for the 700 auto tranny

no vibration....worked fine for 8+ years, other problems, but not to do with driveshaft/vibrations.....the switch to the 200 4r I just eyeballed it, and figgered about an inch differance in mount height, and sure enough the tranny sat on the thwart directly allmost perfectly aligned with the rear holes to the old mounting plate/shoe....

works fine......

 

[SIXFOOTER]

So what should the side to side angle be? When I mounted my 2004R I just dropped it in where the 350 was, but it doesn't look straight.
Hope I ain't gonna get a problem with this

 

[mrvette]

So what should the side to side angle be? When I mounted my 2004R I just dropped it in where the 350 was, but it doesn't look straight.
Hope I ain't gonna get a problem with this

That's an interesting comment, was it Norval or who?? that commented on the lateral of the tranny mount was enough off that it put stress on the driver's engine mount, and made mount replacemet very difficult....
I have noticed the problem in this car, and have had 3-4 driver's engine mounts....so that makes me wonder just where the problem lies, and WHY?? did GM screw up?? possible, but long shot...so what changed?? I dunno...


you wear glasses, I can say this....as a carpenter/cabinet maker/construction guy I hate my damn GLASSES, they make everything look outta square, I can't see 90* no matter what.....or grab my framing square, I kinda used to it, but in other kinds of work, it drives me crazy too....so serious.....remove your glasses....if you got em...

 

[SIXFOOTER]

Well, when I mounted the thing and got it all bolted up and was standing there admireing my handywork, I noticed the engine/Tranny did not sit square in the frame, the tranny tailstock was off to the pass side about an inch or 2. When I fabbed the rear tranny mount, I just fit it up from where the 350 was without moving the motor around.
If I have to move the thing more to the center, I will likely have to remove and remod the mount, that will suck.

 

[mrvette]

Well, when I mounted the thing and got it all bolted up and was standing there admireing my handywork, I noticed the engine/Tranny did not sit square in the frame, the tranny tailstock was off to the pass side about an inch or 2. When I fabbed the rear tranny mount, I just fit it up from where the 350 was without moving the motor around.
If I have to move the thing more to the center, I will likely have to remove and remod the mount, that will suck.

6' you know, it was not all that long ago the topic was mentioned in a thread.....damnit I can't rmember who commented on the fix about moving the mount on the driver's side...making a plate and effeictively shifting the engine bolt holes....but it releived stress on the rubber....
which makes sense to me, but from all observations I can't see where my car was ever hit, the frame measures up correctly on wheel alignment, the weld seams are not showing crash marks/straightening stresses, overwelds/etc....so I dunno...

 

[Strider]

That's an interesting comment, was it Norval or who?? that commented on the lateral of the tranny mount was enough off that it put stress on the driver's engine mount, and made mount replacemet very difficult....
I have noticed the problem in this car, and have had 3-4 driver's engine mounts....so that makes me wonder just where the problem lies, and WHY?? did GM screw up?? possible, but long shot...so what changed?? I dunno...


...

Yes it is me constantly harping about the drive line alignment being off in our vets. I believe in stringing a driveline and lining up the crank/tranny/driveshaft and pinion. All in a line.
I have also taken alot of abuse over this but I believe in it. I did it and I DON'T have a single vibration anywhere, any speed.
It solved a severe vibration I use to go through. This vibration would start at 60 to to 70 , fade away until 90 and then come back extremely strong. I strung the car, cleaned up the misalignment and the car is dead smooth to 130 mph where I quit most of the time.
I also believe in getting rid of the stress on the drives motor mount and make it a slip in or out deal with no side loadings.

 

[Strider]

6' you know, it was not all that long ago the topic was mentioned in a thread.....damnit I can't rmember who commented on the fix about moving the mount on the driver's side...making a plate and effeictively shifting the engine bolt holes....but it releived stress on the rubber....
which makes sense to me, but from all observations I can't see where my car was ever hit, the frame measures up correctly on wheel alignment, the weld seams are not showing crash marks/straightening stresses, overwelds/etc....so I dunno...

Again it was me Gene. It was me. I ran posts on this

 

[MYBAD79]

Great info guys, thanks a lot. I read that long post from 2003.... Lots of good info, stringing the driveline seems to be the way to go, unfortunately it is a LOT of work getting it perfect....

 

[SIXFOOTER]

Thanks Norval, so the whole thing should be dead in line front to back?
that means I got some more wrenchin to do, maybe a lil cuttin and drillin too

 

[Strider]

Thanks Norval, so the whole thing should be dead in line front to back?
that means I got some more wrenchin to do, maybe a lil cuttin and drillin too

I believe this, my friend Roger who runs a sucessful race car shop believes this and yet you will get those on this forum that don't. They believe there should be a mismatch side to side as well as up and down.
Those individuals have yet to say their piece.

 

[SIXFOOTER]

Thanks Norval

 

[yellow73sb]

I could see it helping the weight balance

Anyways I don't feel like lining everything up :laughing:

 

[mrvette]

I could see it helping the weight balance

Anyways I don't feel like lining everything up :laughing:

Y73bb, Yeh I hear you, but that side loading thing on my car putting stress on the dirver's side mount....well, when I think about it, the 200 4r tranny being about 3/8 or so inch to the rear of the thwart mounts...makes me wonder that IF that was totally eliminated by letting the PASS side mount move toward the engine rear....that would pull the engine forward about 3/8 inch on the driver's mount, rleeiving any f/b stresses, which there are plenty the mount wanting to pull the train forward....ok, so I take that as a clue on MY car to releive the pass side mount, and let the thing align itself via the tail mount and the driver's mount, and then drill/releive the mounts on the PASS side....I would hope there is enuff metal there in the mount itself to elongate the bolts and slide it rearward 1/2 inch or so....

OR, it's welding time....

since the engine torque side is on the driver's....long as the pass side held up it's side of the deal, seems to me maybe playing with the mount horn maybe easier....I gotta look at it....

another project....eh???

hummmm....

 

[Strider]

The normal way to change mounts is to release the tranny mount then do the passengers side 1st, then the drivers side and then pry the tranny mount into position and install the bolts.
The hard way is the passengers 1st, then the tranny and then fight with the drivers side. Many have complained that it is bitch to get the drives side aligned and start the bolts. Bernie?????
A 3 of my mounts fall FALL into place, no prying, no hard to start bolts.
I have a tool that goes on the front of the pinion yoke and it has a percision ground rod that slides forward through a reamed hole and it allows me to rotate the pinion until it is pointing directly at the output shaft of the tranny.
Side to side I have no misalignment but up and down I have about 3 degrees or something like that. Haven't measured in a while.
Just got back from a run with my new 540.:thumbsup: :thumbsup:

 

[Kid Vette]

Just got back from a run with my new 540.:thumbsup: :thumbsup:

And. . . .? Details please.