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Chris@Rvengeperformance
09-25-2011, 11:07 PM
I'm going to be replacing my bellhousing and anything else I find busted inside my trans. Can anyone walk me through re-setting the pre-loads?

I've read just about every thread on the old site, about the solder and shim setting. There are a lot of mixed opinions.

Will someone explain what has worked for them?

If anyone knows the rotating torque of the different shafts with the trans in neutral that would be really helpful.

thanks

Intropy
09-26-2011, 12:51 AM
Put a few strips of solder under the outer race (no spacers), then assemble and torque it down. Take everything back apart, pull the races, and measure the solder thickness. That tells you the play - let's say it's 1.0 mm.

In the manual are the recommended preload ranges for each shaft. It will be something like 0.10 mm - 0.20 mm. So with a gap of 1.0 mm, you need anywhere from 1.10 mm to 1.20 mm of spacers to be in spec.

TurboSinceBirth
09-26-2011, 08:29 PM
Where can you order the shims from?

stealthee
09-26-2011, 09:18 PM
I've heard of people cutting up aluminum cans and using them as shims.

Is it safe? I don't kmow, but it's just something I have read in the past.

J. Fast
09-26-2011, 09:36 PM
When following the soldier method, make sure you clock the transmission several times with the soldier in place. I use an old clutch disc and rotate it several times. It will center the helical gearmesh and give you the most ideal preload.

When you set your shims check the overall play between the input shaft and the output shaft with a dial indicator. The smaller the reading the more ideal the gearmesh and the less likely you are to have problems with blowing the bellhousing and endcover ( from the gears climbing).

The overall dial indicated measurement between the input and output is more important than the preload on each individual shaft. The overall measurement will dictate how the gears are meshing and the tooth alignment. Keep shimming each race in 1/2 till you get the smallest overall dial indicated number from input and output in conjunction with the best lowest "average" on the individual shaft preloads. You may have an out of balance shimstack at the races to get the ideal gearmesh say .5mm on one end and .2mm on the other, that is completely normal.

I find most problems occur when rebuilders split the overall shim-height evenly between the bearing races. I can see their reasoning as the shaft is centered. However, you're not trying to split the difference, you're shimming for ideal gearmesh. That's what keeps the transmissions from blowing the covers.

You can buy shims from Transtar or from any local specialty bearing supplier. Provide them the inner and outer shim diameter, and the height you are looking for. They are roughly $5 ea.

q2418130103p
03-18-2012, 08:03 AM
Reading the manual, and checking the transmission as it was from the factory, all the shims appear to be on one end. The end where they call for you to place the solder.