PowerTrax Grip Pro - Salisbury LSD 3.54 Ratio

Just starting to reassemble a '66, 2+2 IRS and have a question on gearing. Will the above gears fit my 66? I have minimal experience with gearing. The existing gears seem ok (no signs of cracked or chipped teeth on pinion or ring gears) but do have 90,000 miles on them. Someone just gave me the PowerTrax described above, complete with gears & bearings, all brand new in the box. Looking for suggestions, it is worth it to switch to the new? Does the PowerTrax offer an advantage or disadvantage over the OEM setup?

The diffs in ETypes are very robust and I’d really doubt if it’s worn out or even anywhere near that. As to swapping it out for what you were given you’d have to supply a lot more info. For example how comparable to the original is the case and it’s multiple mounting points. If not in a case will it fit a e type case and hook up to the output hubs and input flange.

Thank you Terry. It is not in a case and as you suggest, the existing does not seem worn. The numbers do match in that the existing is B66 and the tag is 46/13. So it’s the same ratio. I’ll save myself some work and put it up as a spare.

I doubt the Powertraxx is a complete differential…just the anti-spin clutch and the ring carrier assembly, plus a gear set. Other than the ratio, do you know if you have a limited-slip rear?

Yes, I do have limited slip. Both wheels turn same direction when input shaft is turned.

Then it’s a lot of work and probably gets you nothing.

I was coming to that conclusion too. Thanks for your words of wisdom.

Hello Jim,
Its likely the ratio of the gearset you’re currently running is taller than the 3.54; accordingly, I doubt that you would be pleased with the end result in terms of engine revs and speed over the ground.



Keep in mind the diff is a Dana 44 so parts are not rare.
At least i believe the 66 is same basic diff as my 62.

Thanks Layne. I’m going to utilize the original and keep the new one for a spare.

Its a Type 2 Salisbury differential.



Thanks Bill, yes I see the difference. Saw another thread on the forum that explains the differences and cross over of parts and the Salisbury Splicer/Dana connection. Always thought it was pure 44 inside.