Guibos and Driveshafts

[gidgaf]

I was just watching a British show called "Wheeler Dealer".
The guy had bought a 1968 Lotus Elan to fix and flip.
One of the issues was a lack of power transfer from the engine to the diff. The mech took a look at it, and determined there were bad rubber doughnuts between the flanges. He gave a quick explanation as to how they worked, and why you need to replace them every so often. They also mentioned it was the one Achilles heel for the car, and a common problem.
As he disassembled the driveshaft, the flanges seemed identical to my 1986 528e driveshaft ends. The guibos looked identical, also.
At a nearby Lotus shop, the owner explained that not only were the original design somewhat flawed, almost all of the "new" replacements were actually just somewhat old stock. They made a lot of them. so by the time you bought a new one it had already been deteriorating.
The replacement design was just over double the guibo replacement cost. It was two sets of CV joints. And it should outlast the rest of the car, instead of being replaced every 50k miles. Which nobody did, usually it's drive it until it breaks, then tow it to the shop..
I thought it was interesting, and maybe good for more followup.

[turbodan]

The problem with CV joints is that they don't absorb any shock. Thats what the flex disc is good for.

[Xenocide]

^ Which is arguably one of the reasons that these transmissions are so hardy.

[mooseheadm5]

Two flex discs (or more) is too many degrees of freedom. BMWs use one flex disc and then u joints or CV joints (and occasionally, no flex disc at all.) That is why the guibo on a BMW lasts so much longer than on an Alfa or Lotus with multiples.

[tn535i]

The only time I've seen a ujoint or CV up front on a BMW driveshaft was with an automatic transmission. I this case the torque converter and wet clutches probably absorb driveline shock pretty well.

Can't imagine that a guibo's in the rear drive axle could handle the amount of torque that even and eta can deliver which is about 3x the driveshaft torque or more.

[turbodan]

The F30 3'er and maybe some other models have one on each end of the driveshaft. I like them better than CV joints. No maintenance required, cheap to replace.

[dsmith]

My E320 had front/rear too. Yes, no u joints to wear out. Just replace the cheap flex discs every 150k miles.

[gidgaf]

If there's anything I do know it's that I don't know.
I've owned a lot of Detroit Iron that had a spline at one end of a solid one piece shaft and a Ujoint at the other. The only mechanism for absorbing driveline shock was spring wrapup from dropping the clutch. I've had a few busted Ujoints, and replaced many.
There is also a OEM BMW option that replaces the front part of the driveshaft with a Ujoint and a four bolt flange. Which bolts to a different replacement output flange, obviously.

Part of the other guibo's job is to adapt the angles from the trans output flange to the driveshaft flange. Which a pair of CV joints would also do very well. I'd believe some people go thru a lot of guibos because of misalignment over excessive horsepower.

I've lurked a few other boards since then. There's quite a few Lincolns, Cadillacs, Camaros, etc with guibos just like ours. *JUST* like ours; most folk seem to agree they're made by the same company.
And depending on the vendor, you could be getting a brand new in the box five or ten year old part. That was the issue brought up about the Lotus Elan- the brand new "factory" guibos and other parts were made over twenty years ago. If you really wanted a good and new part you had to buy aftermarket.
Which is my concern. My only ever brand new car was a Ford
POS LX Taurus. Many of the new replacement parts for the car were made about the same time as the car. I bought new motor mounts, and found they were older than the car.
I have an 1986 BMW. My brake pads and water pump were placed in their respective boxes more than five years ago. I just put in a new timing belt a few months ago, and it was three years old when I got it. I wonder what it's theoretical usable lifespan really is.
And now ... I'm looking at buying a guibo. I probably won't get the CV version. But I *am* seriously looking at the orange plastic replacement. At least it'd be new. This year new. And heavy duty.

[Kyle in NO]

There is also a OEM BMW option that replaces the front part of the driveshaft with a Ujoint and a four bolt flange. Which bolts to a different replacement output flange, obviously.

Sorry, but this simply is not true. Some of the auto trans BMWs such as the E28 will use that type of flange on the transmission, but its nothing "optional", unless you are talking about transmission choice...

[Brad D.]

There is also a OEM BMW option that replaces the front part of the driveshaft with a Ujoint and a four bolt flange. Which bolts to a different replacement output flange, obviously.

Sorry, but this simply is not true. Some of the auto trans BMWs such as the E28 will use that type of flange on the transmission, but its nothing "optional", unless you are talking about transmission choice...

I'm with Kyle. I've never heard of such an option. There is nothing wrong with a guibo. The one in my turbo car has held up for over five years of abuse.

[MicahO]

Thank Antonio for the Giunti Boschi

The funny thing is that 90+% of the time, the part's name is misspelled. So at what point does the misspelling become "correct?"

[tn535i]

There is also a OEM BMW option that replaces the front part of the driveshaft with a Ujoint and a four bolt flange. Which bolts to a different replacement output flange, obviously.

Sorry, but this simply is not true. Some of the auto trans BMWs such as the E28 will use that type of flange on the transmission, but its nothing "optional", unless you are talking about transmission choice...

I know it's not true. I looked at converting a u-joint transmission back to a guibo in order to use the original driveshaft and it's not just the output flange that is different but the whole tailshaft of the transmission. When you see them side by side you realize they just made some one way and others another. Who knows if it was BMW or ZF who couldn't make up there mind when and where to use which one but even Bently, BMW fans and replacement sources can't tell you for sure, you have to look to know which you have.

[gidgaf]

> it's not just the output flange that is different but the
>whole tailshaft of the transmission. When you see them
> side by side you realize they just made some one way
> and others another
Yeah, I thought I said that in the trans output flange. I didn't mean "optional" as in an order checkoff list. I meant as in the worker reached behind and grabbed the part that fit the piece in front of him; four bolt flanges got the Ujoint and the three bolts got the guibo.
*sigh*
ANYway, as I was looking thru the 'Net for a new guibo this had come up. Realoem shows both driveshafts, and both trans output flanges; this is for 4HP22/24 *automatics*.
Some automatics just didn't come with the guibo, but the Ujoint "option". And some were converted from guibo to Ujoint later. Some may have gotten a thicker (replacement) guibo, some may have gotten the vibration dampner delete.
Some web sites did state to get under and look first to make sure you know what you had before you started ordering parts. The factory could have issued the automatic model with the guibo or the Ujoint assembly, and there may have been many mechanics and more than one other owner betwixt then and now. What you got ain't may not be what you had, or what you thought.
It's my wife's car- and it's an automatic. I'm going under.
Any official recommendations for the thicker and/or plastic guibo?

[Jeremy]

Your reading comprehension leaves something to be desired.

Yeah, I thought I said that in the trans output flange. I didn't mean "optional" as in an order checkoff list. I meant as in the worker reached behind and grabbed the part that fit the piece in front of him; four bolt flanges got the Ujoint and the three bolts got the guibo.
*sigh*

At this point you seem to understand the situation.

ANYway, as I was looking thru the 'Net for a new guibo this had come up. Realoem shows both driveshafts, and both trans output flanges; this is for 4HP22/24 *automatics*.
Some automatics just didn't come with the guibo, but the Ujoint "option".

Manufacturing variance, not an option as such, but yea, ok.

And some were converted from guibo to Ujoint later. Some may have gotten a thicker (replacement) guibo, some may have gotten the vibration dampner delete.

Multiple people have told you that it isn't possible, why do you keep trying to claim that one can be "converted" to the other somehow? There is no "conversion kit" or "conversion parts" to change a driveline with guibo to one with a u-joint or vice versa. The only option in that regard would be removing the transmission and driveshaft and replacing both with the option you prefer. That's an awful lot of trouble for something with extremely little tangible benefit.

Some web sites did state to get under and look first to make sure you know what you had before you started ordering parts. The factory could have issued the automatic model with the guibo or the Ujoint assembly, and there may have been many mechanics and more than one other owner betwixt then and now. What you got ain't may not be what you had, or what you thought.
It's my wife's car- and it's an automatic. I'm going under.
Any official recommendations for the thicker and/or plastic guibo?

Recommendations for what car, exactly? You haven't told us what car you're talking about.

[gidgaf]

Sorry- my bad. It's a 1986 528E A

>Your reading comprehension leaves something to be desired.
I believe we're having parallel conversations, just slightly related.
I understood what I said, and what I read, however off topic.
> At this point you seem to understand the situation.
I understood it before the beginning. And I understood much more later.
> Manufacturing variance, not an option as such, but yea, ok.
You say tomahto, I say burger condiment. Whatever.
> Multiple people have told you that it isn't possible,
Multiple other people have also told me it has already been done.
Realoem shows me two different driveshafts for my car. One with a flex disk, one with a ujoint.

*sigh*
This whole project started with a simple diff change out.
After I pulled the back of the DS out, I decided to replace the center support assemblage of parts.
I thought I ought to check out the guibo whilst I'm there.
At this time I watched that Wheeler Dealer segment on TV, and I brought the matter up as an interesting topic.

One of the issues *I* still have is I don't want to buy a brand new fifteen year (or older) part. I have already bought "brand new" old parts- like brake pads, water pump and a timing belt for this car. I am going to replace the guibo with a guibo- with a good *new* part. Many folk have also mentioned that as your trans and engine mounts degrade, their looseness and droop will add stress to the guibo. ie: The first one lasted 100k miles, the second lasted 30k; it was the rest of the slop that killed the first one, also. Most of these guys changed these mounts at the second guibo change out; I will replace the trans mounts at the same time, and be done with that end. A few others also washered down the back diff mount to raise the forward angle.

I know Land Rover people with D2s with the same issues, and I know a couple that used a kit that replaces the (very similar looking) guibo and flange with a ujoint. Since 2006 the factory made a kit that uses CV joints for their LRs; theoretically they also have less power loss and heat generation caused by the angular translation as well as three times the expected longevity. Epecially after the recall and the failures, people have looked for 3rd party engineering to fix this, and the rumors are that the factory looked at these trials and tribs to make their own designs. (*MY* car is a 4wd Bronco, and we all hang; plus the LR front (with guibo) is a BMW design). Other sites where I've shopped for guibos have mentioned that some (automatic) BMWs were made without flex disks, and some were also converted. It may be like the odds of getting a 528e with a factory LSD diff- theoretically they do exist, and they're out here. Amazingly there's also places (like one called "The Driveshaft Shop") that has replacement/ upgrade driveshafts for cars, including a guibo delete one piece driveshat for an E30.

And none of that matters to me. I'm going to replace my old guibo with a new one. I understand it's purpose, design and function. A new guibo, with new bolts, and new trans mounts, should last me a very long time. It's a stockish 528E, I'm not worried about horsepower issues! If a poly one works, and lasts longer I'll get one. If there's another BMW model with a thicker more heavy duty OEM guibo maybe I'll get that one. If I had an E30 I know I could get an E46 guibo; it's 5mm thicker which equals the vibration damper. Too (wide) big for my E28.

[Jeremy]

One of the issues *I* still have is I don't want to buy a brand new fifteen year (or older) part.

No worries there, this isn't a Lotus.

Some of the parts may be NOS, but I doubt any of them are 15 years old. There's much higher parts demand and turnover on BMW parts, particularly parts for a 528e, which BMW made a whole bunch of. The guibo also happens to be same as the part for a 524td, nearly every e30 made, the Z3 1.9, and even the r60 MINI Countryman (go ahead, do the cross reference on 26111225624), so the odds of getting a really old guibo are truly slim.

[gidgaf]

> nearly every e30 made
Well, you have roundaboutly kinda answered my question, sorta.

In THAT case, an E46 guibo (#26112226527) is the same size bolt circle and bolts, the heavier duty model, but it is 5mm thicker.
That is the thickness of the vibration damper. Which I'm deleting because 1) it's shot- it's more of a dirty stained plate, 2) it's expensive, 3) most folk seem to think it's useless, D) it's 5mm, and 5) realoem doesn't show it for the E30 or Z3 anyway. If BMW decided to delete it then it's OK by me.
So, that's what I'm going to do: replace the tranny mounts, replace the guibo, delete the damper, replace the center bearing, and replace my halfshaft boots. This should get me around the block once or twice.

Thank you forums and posters! I did look at other forums, and after a little more pieces of the puzzle someone there will always suggest to look here.
I also keep noticing that for everything I fix, there's one or two other things done by someone else I need to fix, too.

[tn535i]

I expect your efforts will generate some improvement and I think you should replace the guibo. You might want to consider the often overlooked centering bushing on the driveshaft as well. To that point I don't know if the engagement will be correct with a thicker flex disc, probably OK. I know there were two discs used on e28/e30's but the difference was bolt circle diameter. Was not aware there might be thicker units? Having the just right bolts is probably important since there usually isn't much extra room between the flance and trans castings.

The center bearing can be a pain to get free but new ones usually slide on easily. Probably also a good idea to replace if D/S out. Remember to pre-load forward.

However, realize also that all new parts parts you've discussed will not help or increase the life of the remaining 2 u-joints. If/when they decide to go bad you're back in there. Too bad these items are inexpensive while a rebuilt D/S is hundreds of dollars. IF it were as simple and easy to replace the u-joints I would do it every time also.

Hope it goes to plan,

[a]

Both of my 86 528e As had the 3rd u-joint instead of a giubo . Both drive trains outlasted the bodies due to tin worm and teen agers . I never had cause to learn much . My experience with the giubo on the 88 528e A is limited to replacing the BIL's . He drove on it until it looked like a ball of yarn It clunked a little on up shifts but otherwise drove OK . There is an early and a late thing with the 4 HP22 tail shaft. The out put is longer and you can't mix parts , I tried, so did Foamy. Doesnt work. Sad to say , I scrapped the 86s last summer. The Grape came to us with a dealer installed drive shaft when purchased in 2K. I don't worry about giubos' age, belts either . I use Conti or Febi. I have had great luck with GMB water pumps. As a daily driver/ commuter/ college beater, the 528e A is unsurpassed. Modern, wrong wheel drive appliances do these tasks better perhaps, but they are soulless .

[Jeremy]

IF it were as simple and easy to replace the u-joints I would do it every time also.

The upshot is that I've never seen or heard of a BMW drive shaft that needed to be rebalanced. I think that might be at least part of why BMW does it that way.

[Bill in MN]

This harkens back memories of my one piece drivehsaft experiment. It destroyed the car when it twisted in half and practiced pole vaulting at about 80.

The Spicer U joints I put on both ends were all well and good but driveline flex wound up weakening the shaft it to the point where it twisted in half.

I am now a big fan of guibo's.