1978 later model differential rebuild

[red]

I have a 1978 spider with a later version rear opening differential. It was noisy so I am rebuilding it. I also am changing the gear ratio at the same time from 10/43 to 10/39. My question is about the side load shims in the diff to each axel side. Will changing the gear ratio significantly change the shim sizes ???? I took out shims measuring 6.8mm and 7.1mm The range of shims listed at Midwest Bayless are from 6.52mm to 7.5mm. With the diff gears in place and the proper backlash adjusted and the gear pattern looking nice I have a much thinner 2.65mm on the left and a much larger 10.92 on the right. Is this acceptable or expected with the gear changes and bearing replacements ??? The total of the two side shims is as expected but the internal gear unit seems to have shifted to the left about 4mm

Thanks for any input
RED

[djape1977]

every bearing and or gears swap requires re adjusting diff. in most cases changing shims as well

[TwinFast]

I have a 1978 spider with a later version rear opening differential. It was noisy so I am rebuilding it. I also am changing the gear ratio at the same time from 10/43 to 10/39. My question is about the side load shims in the diff to each axel side. Will changing the gear ratio significantly change the shim sizes ???? I took out shims measuring 6.8mm and 7.1mm The range of shims listed at Midwest Bayless are from 6.52mm to 7.5mm. With the diff gears in place and the proper backlash adjusted and the gear pattern looking nice I have a much thinner 2.65mm on the left and a much larger 10.92 on the right. Is this acceptable or expected with the gear changes and bearing replacements ??? The total of the two side shims is as expected but the internal gear unit seems to have shifted to the left about 4mm

Thanks for any input
RED

I also have the same problem when i try to change the gear ration on my 1978 Spider from my broken 10/43 crow/pignon to 10/41. I finally buy another crown and pignon with the same ratio, of 10/43 and it work fine. For the shims, i don't think that it's a good solution to have an important difference between the right and left side. The torque is too important, and you could broke your differential