When my mechanic went to install my new Spec 3 clutch, we discovered the input shaft bearing on my HM282 Getrag 5-speed was bad. We finally found a 282 bearing/sincro kit through midwesttrans.com on e-bay (mantrans). But the kit is for the Getrag 282, from 1992 and later, which does not have the old style input shaft bearing (with the throw-out bearing extension). So I had to buy the last one from tim@fieroparts.com (much thanks to you guys on this forum!) Any-way, all is good, just put everything back together...right? Not so fast! When we went to install the new clutch, we discovered there was no pilot bearing. This is not good...maybe that's why the input shaft bearing went bad...??? Can any of you experts shed some light on this? Is there a pilot bearing for the Getrag? If not, why not? If yes, does anyone have a part number? Our GM exploded diagram doesn't show any. If Fiero owners are installing new clutches without one, maybe that's why the Getrag MH282 is prone to the input shaft bearing going out...??? Give me your expert advise please. Rodney Dickman's article mentions the input shaft bearing prone to failure, but I haven't heard anything about the pilot bearing. Thanks.....

Correct, no pilot bushing/bearing. All V6's regardless of transmission don't have one.

[This message has been edited by phonedawgz (edited 08-13-2010).]

GM Transverse engine/manual trans combos do not use a pilot bushing. To my knowledge no other manufacturers do either, at least I have not come across one yet. If you look at the length of the input shaft you will see that it does not extend far enough to reach a pilot bushing in the crankshaft.

Fieros don't have pilot bearings. The input shaft bearing performs that function.

My mechanic, James, who is a Fiero expert (for the most part) had never gotten into Getrags before, so we are both learning here. But he said the Isuzu has a pilot bearing. Seams to us that there should be one for the Getrag! Maybe, as I said, that's why the input shaft bearing is prone to failure....make sence yes? Is there a possibility of one installing a pilot bearing anyway?

[This message has been edited by hypo327 (edited 08-13-2010).]

The Isuzu 5 speed on the Fiero doesn't use a pilot bearing either. Like others have said, these transaxles were designed without the need for them. If you look carefully, most don't even have a machined journal at the end of the input shaft to mate with a pilot bearing. Those that might have some sort of snout on the input shaft are too short to reach the hole in the end of the crankshaft where you would normally install a pilot bearing.

quote Originally posted by Bloozberry: The Isuzu 5 speed on the Fiero doesn't use a pilot bearing either. Like others have said, these transaxles were designed without the need for them. If you look carefully, most don't even have a machined journal at the end of the input shaft to mate with a pilot bearing. Those that might have some sort of snout on the input shaft are too short to reach the hole in the end of the crankshaft where you would normally install a pilot bearing.

Okay...gotcha. But it sure sounds to me like they should have one to prevent that input carrying all the load. I gotta ask James about his putting one in the Isuzu. Maybe he'll have time to comment on this discussion. It makes sense to me that if a person could some-how install, even a small bearing, it would help the input bearing from going out. Make sense?

The pilot bearing topic comes up from time to time. The short version is there is no need for them on the fiero manual transmissions...

Where people get all worked up is the fact that Fiero Store sells one and there are plenty of other sources that say it should have one... and they are all wrong. I suspect where this all comes from is the versitility of which the 2.5 iron duke was designed with... It was GM's mainstay economy/light power engine in the late 70's/early 80's and was put into a vast array of GM FWD & RWD applications, boats, fork lifts, generators and used by others car mfg's (like in jeeps). To accomodate this versitility, there is a group of crankshaft inserts that are used and identified for these various applications. At some time the list became incorrect and people have taken it as fact w/o checking the actual application for validity.

The main reason the GM FWD manual transmissions do not need them is because their input shafts are full supported via 2 bearings (one at the input seal and the other deep inside the case). Conversely, the RWD applications only have a single bearing within the tranny and MUST have a pilot bearing to stabilize the input shaft. On the automatics both FWD & RWD, the torque converter need some type of centering/alignment bushing to help stabilize it since is rests on the shaft and is only supported by 1 bushing/bearing inside the tranny.

Furthermore, if you look at the ends of the input shafts, the RWD versions have nearly 1" of machined surface for the pilot bearing to ride, but the fiero transmissions have between 1/8 -to 3/8" of machined surface... not hardly enough for a bushing.

If you are not convinced by now... then take out your tape measure and measure the protrusion of the input shaft vs. the engine/tranny bellhousing surface to see if the input shaft is even long enough to go into the crankshaft... some of the trannys the input shaft is actually recessed back from the bellhousing face.

If you want to read an epic thread on this subject...
https://www.fiero.nl/forum/A...100421-2-096400.html

Older (RWD) manual transmissions had only one bearing on the input shaft. That is why they use (had to have) a pilot bearing. New transmissions like ours have 2 bearings on the input shaft and thus do not require a pilot bearing. Adding one would most likely cause premature failure of something.

------------------
Rodney Dickman

Fiero Parts And Acc's Web Page:
All new web page!:www.rodneydickman.com
Rodney Dickman's Fiero accessories
7604 Treeview Drive
Caledonia, WI 53108
Phone/Fax (262) 835-9575

quote Originally posted by hypo327: I gotta ask James about his putting one in the Isuzu.

I think all 4-cyl Fieros crankshafts use an insert which is intended to center the flywheel. That insert is commonly mistaken for a pilot bushing. It is not a pilot bushing because the transmission input shaft does not extend far enough out of the transmission housing in order to come in contact with it. If you read the thread that FieroGuru linked to you will see an example of how that insert gets mistaken for a pilot bushing and yet how important it is with respect to keeping the flywheel attached to the crankshaft.

Thanks fellas, I'm really getting an education here. What you say makes sense when explained. That must be what James is thinking of , the bushing for the iron duke. He owns two or three of them. Thanks a bunch. I guess they just needed to make a stronger input shaft bearing to start with. My car has only a little over 100k on it. But my son's '85 GT has well over 200k and still going stong. Mine is actually going stronger, but at least he still has his old input bearing. But then again he had the 4-speed, and only recently put one of James' rebuilt Isuzu 5-speeds in it. They both have better bearing designs maybe? Gotta say, I love my Getrag, as far as vintage 80's 5-speeds go.

Does anyone know if the newer post-91 and up, Getrag 5-speeds are a better transmission? At least one can still get parts for them. I will have an extra input bearing for one, after this overhaul of my MH282. Maybe it will go another 200k now.

a special thanks to you Jefry for putting me onto that bearing/sincro kit.

[This message has been edited by hypo327 (edited 08-13-2010).]

quote Originally posted by hypo327: Does anyone know if the newer post-91 and up, Getrag 5-speeds are a better transmission? At least one can still get parts for them. I will have an extra input bearing for one, after this overhaul of my MH282. Maybe it will go another 200k now.

I consider the 92-94 FWD getrags to be the best of the 282 model line...
https://www.fiero.nl/forum/Forum2/HTML/091336.html