Powertrax more play at pinion yolk?

[liquidh8]

I have a 9 inch ford, 31 spline moser axles. Stock 3.50 gears. After putting the power trax locker in it, and setting the ring and pinion backlash, there seems to be some more back and forth play at the pinion yolk. Is this a normal occurrence with these lockers? Any have a bunch of experience with them. This is not my first rear rebuild, but my first locker install. It's almost like you have bad spiders. You can move the wheels, or the driveshaft more than stock to get the other to turn.

Thanks guys

[ssealeycpa]

If you are talking about the noticable "Clunk" when on and off the gas, I believe this is normal. I have a 1988 GMC 1 ton with a Dana 70 that came with an open diff (go figure). I put in a powertrax unit to save a couple hundred dollars and it never locked up good (it would spin then lock hard) and had the noticable clunk as if the backlash was too great (backlash was identical after the install since this unit only replaced the spiders). After it aggrevated me for a year or so, I took it to a rear end shop where the guy took it apart, put it back together and said "fixed". I paid him and it acted the same. Long story short, the only locker diff for a Dana 70 was a "Detroit locker". I bought one and the problem was fixed. I have used the Detroit Locker; Tru-Trac and an Auburn locker in my Chevelle. All seem like good units. I had a bad experience with the Powertrax and I would advise someone looking at this as a way to save time and money...think again. That's my 2cents.

[liquidh8]

Yes, the clunk is what I am talking about. Almost like when u have a bad u-joint. I have driven the car yet as I am fixing the body. But I know that clunk would stay. Thank you for your reply.

[chicane67]

Its normal... I drive one everyday... and have installed hundreds of them in various applications.

[liquidh8]

Great, Thanks for the replies guys!