I'm wondering what the pros and cons of using a roller pilot bearing are as compared with stock-style bronze bushing. Will the roller bearing last as long? Someday, when it's old, is it likely to seize up or give weird problems? What are the advantages to a roller pilot bearing?

The roller bearing will hold a more exact position over the life of the bearing. They usually hold up very well. One the lube is gone, it's shot. The bushing is a very special metal with lube built in. The problem is as the lube disapates, the bushing wears. This wear releases more lube. This means the bushing never runs out of lube, but does slowly wear away. The wear allows the trans clutch shaft to wobble. The wobble in not a big factor to start with. As it worsens it can cause wear to the transmission input shaft and input shaft bearing. This will also advance clutch wear. This is not to say the bushing is a bad thing, it's not. They work well for a long time. The biggest thing is replace it everytime the clutch is serviced.
The stability of the bearing eliminates all of these problems, and is generally a better device. Yes it will wear out. When it does the results are much more instant than with the bushing. Again, if the bearing is replace everytime the clutch is service, it usually won't fail. The bearing is more costly ,(not much) and is a better way to go.

Ken Styer

Thanks, Ken, for the explanation. It makes perfect sense. Out of curiousity, if the pilot bearing ever failed during driving, what would happen?

Sounds like the bushing is "safer" with catastrophic failure and stranding in mind, while the bearing is "safer" for your tranny because it won't get sloppy as it gets older. Maybe the best mix is a bushing that's changed often...but is changing it every time the clutch is changed out (not very often) enough to avoid wobble/wear issues that could affect the tranny?

Patricia

I figured since GM uses the needle bearing for their trucks that it was heavy duty. Just a thought.

Marc

Just to add to 73shark's reply.
I remember that GM used them on the 6.2 liter diesels (in pickup trucks)when they came out in the '80's.

So I guess if they held up ok in a noisy, vibrating (and stinky) diesel, they will hold up ok in a high perf engine.
I have a bearing, not bushing in my vette and so far so good.
Sarge

Yes, overall the bearing holds up better, and is better. It will usually operate for the life of the clutch. If either bearing or bushing, is not replaced when the clutch is done, it will likely fail before the next clutch service.

If the pilot (either one) gets sloppy, it puts stress and wear on the clutch disc, transmission input shaft, and the front trans bearing. This is more likely with the bushing. Either may or may not make noise in this condition.

If the pilot starts to stick or seize it can first be noticed with noise. The noise is a squeal or growl, and will only occour when the clutch pedal is down, and the clutch is disengauged. This is the only time the transmission input shaft and the crank shaft turn at different speeds. With your foot off the clutch and the clutch engaged, the two spin at the same speed, unless the clutch slips. The pilot is the bearing between the two. If you hear this noise in this condition, plan on service very soon.

If the pilot sticks, when you try to release the clutch, the crank will continue to spin the transmission input shaft. This makes shifting very difficult, and even more noise. It's like pushing the clutch in only part way, and trying to shift. This is most notable in reverse. All of the forward gears has syncronizers, reverse does not. So the spinning shaft will make the gears grind when shifting into reverse, but forward gears will be smoother. At this point you need to fix it right away, or walk.

Ken Styer

Pilot bearings were used in all Pontiacs, because they were better. Chevy used bushings because they were cheaper. For the enthusiast, the difference between a $2 bushing and an $8 bearing won't affect profit margins and we should use a bearing. That's my 2c. Joe

Thanks everyone for the help. I'll definitely go with the bearing. It makes good sense.

A long time ago a friend ordered a pilot bearing for me (previous car/previous engine). We installed it and it went in just fine, but when we went to put the tranny in it would not seat all the way because of that darn bearing that, apparently, was longer. It took a LOT of work to get it back out! Chisels and hammering and several hours. I don't know why it didn't fit and I find myself a bit nervous about installing another in case the same issue crops up. When ordering the size, is there anything to watch out for or ask about? I notice some ads state "no mods necessary", so I guess with some of them you have to expect modifications. Anyway, I'll hunt for one that really is supposed to be a direct fit. Any pointers appreciated (brand, etc.).

Thanks, Patricia/'75 383

The right bearing should be a direct replacement for the bushing without mods. There are two ways to get the old one out. One is to use a slide hammer with a puller, either a single jaw or the easier to use double jaw. These can be rented at AutoZone. The rental is a free service, full refund when you return it. The second way is to pack bearing grease into the pilot hole and fill the space behind the pilot with grease. Now find a dowel or shaft that fits the pilot hole. Insert the dowel and hit it hard with a hammer, driving it through the hole. The impact creates a hydraulic pressure in the grease behind the pilot, and drives it out. This works very well. One word of caution, if the dowel or shaft fits loose in the pilot hole, you will shoot large quanties of grease in your face, and the pilot will still be there. Don't ask me how I know, but many many years ago I found out. Trust me, you won't make the mistake twice. Very messy.

Ken Styer

Thanks, Ken, for the warning!! :) I likely would have discovered the grease-squirting experience for myself had you not said something.

Patricia/'75