Has anyone ever measured and adjusted axle play? If so how difficult?
Not too difficult but a little tedious finding the correct amount of shims.
These steps should give you an idea of the procedure and assume R&R of both trumpets:
It doesn’t matter which side you do first, this is just how I did mine. Start with the right side trumpet: Use your favorite sealer at each flange junction and on each gasket. I prefer Permatex® Form-A-Gasket® No. 1 Sealant. Put one fiber shim/gasket between the bearing retainer and the brake dust shield. Then put a thick steel shim bracketed by two fiber shim/gaskets between the brake dust shield and the trumpet flange. Slide the assembly in place and torque down the six nuts/bolts that hold the axle to the trumpet. You will likely have about a 1/4" slop when you pull/push on the axle. That's normal.
Now move over to the left side. Assemble all the parts as before except do not use any sealer until you get the correct amount of shims and gaskets. I started out with the same number of shims/gaskets as the right side and wound up changing to a thinner steel shim and adding one more gasket to get the clearances I wanted. What you're looking for is the axles will easily turn opposite of each other with no end play when you push/pull on either axle.
I also held off installing the left, outside trumpet seal until I had the clearances set - you will have to pull the left axle out several times to get it right and I wanted to minimize the risk of chewing up the seal. Note on the seals - Coat the lips of the seal with grease to prevent them running dry until the oil/grease gets to them. I also put sealer between the metal part of the seal and the mating surface you are bolting or driving it on to.
Assembly Order
1. 8N 4229 Paper shim & steel shim combination (always bracket steel shims with fiber)
2. 8N 2255 Brake dust shield
3. 8N 4229 Paper shim
4. 8N 4284 Axle shaft gasket
5. 8N 4124 Bearing retainer assembly
6. 8N 2212 Brake backing plate
7. 8N 4248 Hub seal, retainer & gasket assembly
8. 8N 1171 Axle hub
9. 8N 4293 Washer
10. 8N 4179 Nut and snap ring assembly
Note: The four serrated shank, headless bolts are inserted into the bearing retainer after installing 8N4248 seal retainer assembly. In addition to the headless bolts, you should also have 4 hex head bolts with two being longer than the other. The shorter of the two are installed in the same direction as the headless bolts - The two other longer ones go through the trumpet flange and help secure the bearing retainer to the trumpet.
Upon completion, re-torque the axle nut every 5-10 hours of use until it takes a set and won't tighten any more. If you forget to do this, the hub/axle mating surface will wear from rotating back and forth.
