Diff question

[tr6guy]

Hi, posting a pretty technical question question here and not sure this is the right place for that so, apologies in advance if this is the wrong forum.

I own a 1973 Triumph TR6 and, like many TR6s, I have had numerous problems with the differential in the car. It turns out that with some very simple mods, diffs from 1997-2001 Infiniti Q45s are a good fit. There's even a place that sells the conversion kit. This past winter I sourced a diff out of a 98 Infiniti Q45 with only 57,000 miles on it, cleaned it up, made the mods and installed it in my TR6. Unfortunately, on test drive, the diff is very noisy (whines on deceleration). That, apparently, is very unusual for these diffs.

One of the mods that had to be made was to machine down the input flange on the diff. To do that I had to remove the nut on the pinion, remove the flange, have it machine and then reinstall it with the nut. I thought I did that correctly but with the whining I have to wonder if I messed up the pinion pre-load in the process.

Does anyone know where I might find details on how to properly torque the pinion nut to achieve proper pinion pre-load?
Failing that, any suggestions on how to go about finding a shop in my area (Northern Chicago suburbs) that would be able to diagnose and repair the diff?

[maxnix]

www.nicoclub.com/FSM/Q45

[tr6guy]

Thanks! That was really useful.

In the section on diff assembly/disassembly/etc, it says to torque the pinion nut to "the specified value" but it never says what that value is.

Anybody know what the torque setting should be?

Maybe I should call my friendly neighborhood Nissan dealer and see if they know.

[Infinitiguy19]

Pinion Nut torque: 137-217 foot pounds of torque.

[tr6guy]

Wow! Wide variance. Would seem like a variance of almost 100 pounds would alter pinion pre-load.