411 Diffy

[83Pbass]

My 4A has developed quite a whine, time for a differential rebuild. I have come across a rebuilt 411 diffy vs. the 371 that is in the car now. My TR is non OD and a solid axle. Will the 411 wind up the RPM to quickly for 50 - 60 mph crusing?

Anyone using a 411 differential in a non overdrive car??

Thanks

 

[JerryVV]

A solid axle 4A will be different than a TR4 as it relates to spring mounting. Internals will be the same so check to be certain it's a 4A and not a 4. The gears are 4:10 but that's being nit picking. It will give you better acceleration but will be very buzzy at highway speeds with out OD. Mostly depends upon what kind of driving you'll be doing. If alot of highway you might want to reconsider the 4:10. The engine can handle the revs if it's in good shape and you'll like the acceleration but you will give up some revs for fast road driving.

 

[TR3driver]

My 56 TR3 had 4.10 gears and no OD when it came to me. I hated it, and took a risk on not making TRfest while I installed an overdrive. Later the 4.10 grenaded and I temporarily installed a 3.7 while I build a 3.45 for it. Acceleration with the 3.7 does not seem appreciably slower than the 4.1 even with the alloy flywheel (that went in with the OD).

A fairly obvious difference between the 4A solid axle and the 4 : The 4A unit has a flat pad on the top as well as the spring pad on the bottom. The TR4 unit doesn't (the area on top is just the round tube).

 

[Marvin Gruber]

I have a couple of 4A solid axles rearends if your interested. Just PM me.

Marv