Replacing Guibo

[Tom Bombadil]

Is is possible to replace the guibo on an AT car without dropping the exhaust?
I'd like to think that loosening and sliding back the driveshaft will give me enough room.

[632 Regal]

you might be able to, I mean it could be possible but idonno. I looked at mine, well I tried to look at mine and didnt see a driveshaft, except where it bolted to the rear end and maybe an inch in the front part. the center section is completely obstructed with a shield of sorts. so if you can get past that stuff I guess it is possible.

[mamilapon]

No, you can't. You need to remove the heat shield.You don't have to disconnect the exhaust altogether, just leave it hanging, (supported) and manoeuver the shield around it. Good luck.

[Dave M]

Agreed,

While I've only ever done the job on a manual trans, I can't see it being done without getting the exhaust and heat shields out of the way. Not sure what is meant by "sliding back the driveshaft", describe if possible.

Curious as to what is motivating you to change the guibo? What are the symptoms or visual cues? One thing to note is that if you don't remove the heat shielding, you can't check your center bearing and replace if worn.

See archives for a ton of posts on this subject.

Dave M

[Tom Bombadil]

Sorry, I definitely plan on removing the shields; I just do not want to drop the exhaust if I don't have to.
In my experience BMW driveshafts have a gland nut in front of the diff. When loosened the shaft will collapse a bit, allowing the center pin in the shaft to be retracted from the transmission output.
I was hoping this would be enough to pull the guibo.
It has a hairline crack in it. Nothing to worry about now, but I have the part so why not.

BTW, here is a picture of my dear touring.

[yaofeng]

What is a gland nut?

I just put together a good propeller shaft out of two on the 540. The one from the auto was good. That came with the 6 speed package has a bad center bearing. I used the rear shaft of the auto with the good center bearing and the shorter front shaft of the 6 speed to make one so I didn't have to buy a center bearing.

There are six M14 bolts (M12 bolts for the 525) on the guibo side (three for the shaft and three for the gear box output) and six M10 studs rear of the CV joint on the diff. side.

[Dave M]

Tom,

I don't see it being impossible to do with the exhaust dropped, but from my experience, the least difficult task in removing the exhaust is removing the six manifold nuts (they are a locking nut, so you 'should' replace them). You may have a stud or two spin off, but thas about as tough as it gets. For what its worth, I'd always take the extra few minutes to get it out of the way. You may save yourself a couple of bloody knuckles not having to crack the driveshaft/guibo/trans bolts with it in the vicinity.

Below is a pic of my guibo in case it helps. I still don't gather how 'collapsing' the driveshaft at the diff would help in detaching things at the front end, but I'd love to learn.



Not to discourage you from replacing the flexdisc, but if its only a hairline crack and there are no ill-effects, you may consider waiting. The pic above doesn't do justice, but there were a sea of cracks and chunks of rubber missing, neither of which caused any problems (I think this photo was taken en route to a shift linkage overhaul). Others have posted pics of guibos that are more metal than rubber.

Anyhow, sounds like you've got a handle on it,

Dave M

[Derek A.]

The tech at the shop mentioned that you can drop the rear mounts - support the exhaust - then drop the tranny mounts a bit to gain access to remove the front shaft. No need to mess with the manifold nuts. Still a pain in the ass to do on jackstands.

[Bill R.]

You can seperate the exhaust at the cat and remove the cat, leaving the front part of the exhaust fastened, then unfasten the hangers for the rear part and lay most of it down leaving the very rear on hangers still. Then remove the heatshield, then unbolt the center bearing mount on the driveshaft and the bolts and nuts on the guibo, you can then angle the driveshaft at the center bearing down enough to allow the front of the driveshaft to slip out and then you replace that guibo., paying attention to the marks on the guibo and the bolts. Odds are that your center bearing mount will be on its way out too, so while your in there you may plan on removing the driveshaft from the diff and replacing the center bearing too if needed, and also as far as what Derek mentioned, you have to remove the tranny mount crossmember anyway to get at the guibo bolts on your car. I support the transmission on a jack with a large block of wood spreading the load on the trans pan, while the rear mount is off.

Is is possible to replace the guibo on an AT car without dropping the exhaust?
I'd like to think that loosening and sliding back the driveshaft will give me enough room.