Timken Bearing Mod with no machine work

[Spoonboy84]

A member asked me to post more info on how I did this. This is not an ad. Information for those who can use it. We are in our own garages at home doing what we love and hoping to help others do the same. We got tired of cracking ring and pinions and constantly servicing the trans axle. I am a machinist at my real job and decided to come up with a solution.

I machined an outer race that fits a tapered roller bearing in the intermediate housing that fits on the pinion without having to machine the pinion diameter or the bore in the intermediate housing. It is heat treated and has let our drag car get twice as many runs before cracks started showing again on the ring and pinion. This bearing set up only works for splined pinions with 22mm diameter end and early gear carriers(72 and older type1) with 47mm pinion bearing bore or Mendeola MD4E gear carrier.

Set up is wordy to explain but pretty simple if you have rebuilt a transaxle before. This should be setup after your pinion depth is set and you know what pinion shim you will be using on final assembly. It is similar to setting preload on the other bearings. Press the custom outer race into your intermediate housing(in place of the standard roller bearing) from the direction of the gears toward the nosecone. Assemble pinion shaft complete with all gears as normal, except flip 4th gear to put the larger shoulder toward the nosecone. After 4th gear install tapered bearing (direction to match taper in outer race) and the thick spacer and nut. Now install the pinion and retainer(with whatever pinion shim you will be using for final assembly) into the main case, but don't bottom it in the main case. Just get it in far enough so you can start the bolts on the retainer(or the big nut). Then fit the intermediate housing with the special outer race. Tighten down the intermediate housing to draw the pinion in and torque intermediate housing nuts/bolts to spec. Spin the pinion as you draw in the housing to see if it gets tight. You should feel some drag, but you don't want it to lock up. Make sure the pinion spins with minimal drag. Then set up a dial indicator on the threaded end of the pinion. Zero indicator. Tighten the pinion retainer and record the measurement of how much the pinion moved. Torque the pinion retainer to spec and double check your measurement on the indicator. Start over and recheck your measurement to make sure you get a consistent number. This number is the amount of shim you will need for zero preload. I like .004 preload, so add this to the number, and this is how much shim you will need (behind Timken bearing) for your transaxle. Install the correct amount of shims behind Timken bearing and make sure to torque the nut to correct torque(use red Loctite here). If you have the tools to measure turning torque shoot for 175%-200% what you see from just the standard pinion bearing. Now you are done with the set up of this part and can resume assembly as normal.

I have pictures on our facebook
https://www.facebook.com/17757085526725 ... 1632090281

Any questions you can post here. If I don't get back to you right away our email is [email protected]

[Casting Timmy]

What are you using for shims and how do you keep the bearing race in place inside the nose cone? I assume this only works for the early gear carriers.

[Spoonboy84]

The bearing I used will work for splined pinions with 22mm diameter end and early gear carriers(72 and older type1) with 47mm pinion bearing bore or Mendeola MD4E gear carrier.

I made the bearing race with a flange. It is pressed in from the gear side toward the nose cone. Therefore trapped under preload and can't move. I forgot to mention 4th gear should be flipped to use the wider shoulder for the shims to sit against. Shims are commercially available standard bearing shims. I have thicknesses from .002-.031.

[Casting Timmy]

Definitely a few different gear carriers.....there are 3 upper bearings. 113, 002 and 091 all for the T1. Then a couple pinion bearings down low and combinations both factory and from people fixing over the years.

I'm not as good with the gear carriers as others here, but I know the lower pinion bearing held by a bolt is a straight through hole. Later cases there is a stop from the factory at the bottom and ribs on the nose cone to keep it still.

If you have aftermarket 1/2 gears I would guess you have the 113 bearing and could also use an E box gear carrier from a Mendola if I understand right to get an aluminum housing that's stronger than the factory aluminum/mag gear carriers. I also assume that the E box covers would also already be clearanced for running a big fourth gear.

[Casting Timmy]

You might also search "Keeping your ring and pinion alive" on here for more ideas to help your ring and pinion last longer.

A neat trick I have seen lately is a hydraulic dampener system that only works when in first gear. Although I think I would try more of the slip and preload method if I was going to drag race to get the car loaded.

It's a nice product which should work more with the aftermarket shafts used for drag racing I think as they use the early gear carrier bearing.

[Spoonboy84]

Thanks for the info and correcting me. Always good to learn something new. So it looks like this will only work with 1972 and older boxes. I don't want to spread any mis-information.

I've definitely read up on increasing ring and pinion life and talked to other racers. Just offering what I came up with to avoid machining the pinion and the case to make this upgrade more user friendly.

Thanks for the compliment. It's worked well enough to put up with our abuse. To the point we are now breaking axles and the trans has checked out to be fine. We are trying to run I/Gas (a 7.99 index class) with my buddies "street car". Looks like we need to soften up on our launch to save the axles and find some et elsewhere. We have run some passes in the 7s, but not every track we need to run at.

[Spoonboy84]

I've heard about being able to use the mendeola gear carrier but haven't found to need one yet. Have you heard of anyone breaking a stock one?

We are running the aluminum rhino case with 1 gusset. I've heard they can crack at the drain plug, but so far our case has held up well. We did crack a two bolt nosecone which let the transaxle move enough that the mid-strap put enough force on the main case to crack it where the steel hit near the gear carrier. I welded that and it's still alive. We have over 200 runs on this case and gear carrier. We converted to the newer 3 bolt nosecone since that happened.

[gkeeton]

Thanks for posting the info!