Arial
Some ads for the Tremec TKO 5 speed tranny indicate a roller pilot bearing and some use a stock GM pilot bearing. One dealer told me that is because the mainshaft portion that goes into the bearing is larger than a stock GM and another told me that is not true, that they all fit a GM bearing. Anyone know the difference?

My 500 uses stock bushing and I did not use bearings as I have had some bad luck with them coming apart or wearing out ,, I trust the bronze. If you order for gm , you will get correct input shaft but it will be fine spline.

I was told that the input shaft was a different size (where it goes into the bearing) therefore requiring the roller bearing. This makes no sense since Tremec makes all of the trannys. Some dealers advertise they take the trans apart and "blueprint" them.
I agree that a bronze unit makes more sense. I have heard that roller bearings go because there is no way to get lubrication to them.
Where did you buy yours?

Got mine from Mike Pell, Jam performance. Lube is why I went to the bronze bushing.. and it does not come apart and chew up input shaft.

GM no longer carries the Bronze bushing we were used to ordering. (They still do under a new number that is the same bushing but for older trucks) Tremec recommends the roller bearing because it holds the input shaft solidly in place. They (Tremec) also use a tapered front roller bearing in the front of the transmission. This is why the runout tolerance is .005" in new transmission instalations. The old Muncies used ball bearing front bearings and although the manufacturing tolerance was pretty tight, you could get away with .010" or .015" runout before you started to get shifting problems. There are a lot of old muscle cars on the road with warped bell housings and Muncies that are out of runout spec and will never cause a problem. A bronze bushing will tolerate excessive runout when combined with a Muncie's front ball bearing and a misaligned bell housing. The needle pilot bearing wont! The needle bearing pilot bearing is widely used and does not cause problems if installed properly (within the .005" runout) GM uses this same bearing in the 6.5 Diesel engines. If you use a pilot bushing rather than a bearing on a newer style transmission such as the Tremec, it will allow the input shaft to be un supported at the tip and can cause the front transmission bearing to wear prematurely. I too have seen pilot bearings eaten up and worn out but there was usually a reason for it. A cheap clutch that was not properly balanced from the factory will be very tough on a bushing or a bearing. I cant confirm this but I've been told the Muncie input shaft is not as hard as the newer Tremecs. For this reason I would not use a pilot bearing with a Muncie. Instead, I would use a bushing. I presently use a pilot bearing in my 69 with my TKO 600. I removed my transmission recently to do some clutch work and I checked the input shaft and bearing. With about 4000 miles on the trans, there was zero wear on the input and the bearing was in perfect condition. I put a little more grease on it and re installed the tranny. We'll see how many miles the bearing will last i guess. The bottom line is things are changing and we are all a little sceptical about these changes. After these transmissions have been on the road a while we will all learn how durable the parts are. For now, I'm going to trust the manufactures recommendations and go with a bearing. But your runout MUST be within the .005" spec! If it's not and you have a bearing failure, you can't blame the bearing.
Jim

I also got mine from Mike Pell and I am running the roller bearing that was sent with it.

Jim, not sure if this is the post for it, but how exactly would one "CHECK" the runout? I'll be going with a tko this winter, so I read all the posts on em with a lot of interest. I understand that the trans is supposed to be a tight fit in the bellhousing, and the input shaft should aim dead center (+-.005") for the center os the crank/pilot bearing. I also know that the bell locates on dowels in the back of the block and offset dowels are used to move the bell and correct out of spec runout...

But how the heck would one measure such a thing?

JimM
There are a few good sites you can visit that explains the alignment process. A dial indicator mounted on the end of the crank with the gauge running on the inside edge of the bell housing is what you need to do. If you are going to use a new housing consider using the McLeod because unlike most housings it's designed and machined to be within the factory spec of .005" right out of the box. When you are ready give me a call and I'll help you out if you need it.
Jim

I experianced a bad set of roller bearings and was told to use a gm bronze # 10125896 . True the Tremac has front taper roller and is shimmed in to specs. My lakewood runout was with limits and I used offset dowels to correct to almost 0.0, No problems here. These roller input shaft bearings may have been revised and I can see some need here for a wiper seal to retain the grease in that bearing cup.. Sorta like the one that GM alternators use. When my bearing failed,, I noticed the outer cup in was worn down to expose needles and it lost its lubricant. But I guess my routine inspections paid off as I had no damage to the input shaft. So what I can say here is that it's not a perfect world even when you use the best of everything.

zdld17
I agree that nothing is perfect and bad stuff will happen even if you do things right. The GM pilot bearings and the ones we supply do have a seal. I'm not aware of any that don't. Remember that Lakewood housings are sized at 4.684" and the retainer on a Muncie or Tremec is 4.680" so even if you get your Lakewood dialed in to zero, you will still be out of alignment by .002". If you are lucky enough to get your lakewood dialed in to say .004" you will be beyond the recommended spec by .001" Factory bell housings and McLeod housings are a snug fit with no extra room.
Jim

You are correct about clearance on the front t/o bearing retainer.. When I first put this setup together, I made it all up on the floor, Complete assy into the bell housing.. It was a tight fit but I cleaned up the hole some as I did not want to have to pull this into the bell housing under the car. Snug it is..

I would be interested in your bearing, Is this something you offer ? Non GM?

I will be going to a 600 sometime soon and will have it all out again.. I will be taking my Tk0 500 out and going to 600. Some lucky person or persons is interested. I want to move on from 3:27 to 2:87 first gear. Car screams as it is and I want to slow things down to cruise more ..

GMJim,, ,would you be able to tell me what is the OD of that input shaft,, I will be removing soon and would like to check things out.. Thanks

Fwiw, I installed a stock type bronze pilot bushing I got from O'Reilly's in my 496 crank and it was really tight going in!!

Looking back, I wished I would have chucked it up and ran some sandpaper on it..

pdq67

zdld17
The input is 1-1/8" 26 spline (fine). Our bearings come from McLeod and are good quality.

pdq67

Your bushing MAY have been tight because when you installed it you didn't use the proper tool. Most guys use a socket or a bearing driver and this causes some distortion when it's driven into the crank and the hole closes up. The proper installation tool has a nipple that looks like the input shaft and inserts into the bushing when it's driven in to prevent the distortion.
Jim

Some lucky person or persons is interested.
;)

I did not think my question would spark so much input. Thanks for all the replys. Jim, the tool you refer to instead of a socket with the nipple. Is this a Kent-Moore tool or something readily available through some of the auto supply houses like Summit or Jegs?

Kent-Moore is what I use. Got these from my dealership many many years ago.. You may also use a bearing / bushing installer found Snap-on or Harborfrieght. You may get away with cutting off an old input shaft. To remove the bushing,, I have used my grease gun, the tip fits in the hole well and then pump grease, just pops out , little messy but it does work.

Dan
I use a cut off input shaft I got from an exploded Muncie. I welded a thick washer on it and it works well as an install tool. You can still install the bushing with a socket or bearing driver but it helps to lubricate the crank with light oil and keep the bushing in the freezer right up until you install it. Check for bushing distortion with the clutch alignment tool before you put the tranny in. This way you will know if there is a tight fit, where it is. If you have a transmission shop nearby, you may be able to borrow a tool from one of the guys in the shop. I would usually accept a deposit for about twice what the tool was worth to loan my stuff. This way you get your stuff back, so offer the guy some dough and he will likely help you out.
Jim

Thanks Jim,
I appreciate the info. You do spend a lot of time answering questions on this site, and I am sure I speak for many visitors that your info is helpful and appreciated, although I don't know where you find all the time.
Once again, thanks.
Dan

Thanks Dan
That's nice to hear. I get a lot of good info from other parts of the site so it's a nice trade off.
Jim

I find the easiest way to install this bushing required no special tools ..except a freezer.. put the bushing in the freezer overnight (dry ice works faster) make sure the bushing hole in the crank hasn't any burrs if it does clean it up using some light grade emory cloth. Take the bushing out of the freezer and install it immediately i like to use an old socket or a large brass punch and it actually goes in usually quite easily with just a few light taps

Thanks for the input "shadow". Good idea. There were a number of good ideas and input given on the subject. Apparently the bushing or roller bearing will both work well if the bellhousing is dialed in correctly. I think the commentary given here has debunked the idea that a roller bearing is mandatory. Thanks to everyone who responded.