While I was swapping a bell housings off a transmission (Datsun720(1981-83 720 Truck) to 280ZX type, I happend to lose a metal sim at front counter bearing.

It is located at front cover. I called Courtesy Nissan, they said that there are 4 different thickness, and are national back order(comes from Japan in 4 months!) Now my question is, do I really need it? Sim size could be different depending upon how far I press in the bearing into counter shaft.....

A transmission shop I know told me to use gasket maker rather than thick original gasket to compensate the thickiness......... I am looking for metal sim OD 6.2mm ID 5.4mm. (240Z-280Z ones are smaller in diameter) New or used.....

Anyone has experience or recommendation?

Esprist

The shim is needed to prevent the countershaft from walking forward and backwards under torque loads. The different thicknesses are to accommodate production differences. You want the shim to be a snug fit - it should take up all the play at the bearing, but not preload it. I'd fear that using a non-metal shim of some sort might cause problems eventually.

The shim is needed to prevent the countershaft from walking forward and backwards under torque loads. The different thicknesses are to accommodate production differences. You want the shim to be a snug fit - it should take up all the play at the bearing, but not preload it. I'd fear that using a non-metal shim of some sort might cause problems eventually.

Thank you for your quick response.　Well now the question is who might have the sim..

Esprist　6.2mm　OD　5.4mm　ID