Hooking up with nitrous and a 3200 stall

[BFASTNOTLAST]

So, its hit or miss with motive as you have heard.... However you need to remember the Tru-Trac has its own backlash on top of backlash i the R&P. Don't be alarmed by it it's normal. My rear does the same thing, sounds like its going to fall apart when rocking the wheel back and forth. As long as there is no big debris and only the normal fur stuck to the magnet, run it!

[Joe M 2012 2SS]

Originally Posted by BFASTNOTLAST

So, its hit or miss with motive as you have heard.... However you need to remember the Tru-Trac has its own backlash on top of backlash i the R&P. Don't be alarmed by it it's normal. My rear does the same thing, sounds like its going to fall apart when rocking the wheel back and forth. As long as there is no big debris and only the normal fur stuck to the magnet, run it!

Billy I think the Tru-Trac is fine, it's just the Motive gear whine. It howls like a wolf.
A golfing buddy of mine who also runs dirt track cars took a ride with me and said it sounds "normal" for a Motive. I posted a video in this thread of the gear whine, a few posts back.

Since my car is a daily driver street/strip car, the gear whine is just too much. A 15 minute ride gives me a headache!

I haven't dumped the diff fluid as of yet. I put Lucas 80/90 heavy duty gear oil, non-synthetic, as Eaton doesn't recommend synthetic oil with the True-Trac.

[WoodBoss]

Did you get this sorted out yet?

[Joe M 2012 2SS]

Originally Posted by WoodBoss

Did you get this sorted out yet?

I just got the rear pinion bearing and crush sleeve in last Friday. Also went ahead and ordered a transmission dipstick from Janetty.

I went by his shop today, he has an older Ford (1940ish), a corvette, and a gasser race car on his three lifts. Said probably next week.

He said he may be able to adjust the gear to get rid of the whine, but since I've drained the diff fluid twice and no metal shavings were present either time, he said there is a strong possibility that the gear whine is coming from the gear not being machined properly. Motive will blame it on the previous install even if it is in right, so I'm out the $$ for that gear. Wont ever buy anything from them again.

I could take a chance on buying another gear, or just put the factory 3.27 back in that came out. He recommends doing the latter since that gear never had any issues.

He has a ton of experience with GM differentials, so I'm going to let him do what he thinks is best.

I know I told you that you could have the old gear, and the posi unit, but at the time I did not know I would have all this trouble with the brand new Motive gear, so if he wants to put the 3.27 back in, I'm going to have to do that.

You can still have the posi unit, as I have the true trac in now. But if he wants to put the original gear back in, then I'll have to go that route.

I hope you understand.

[WoodBoss]

Originally Posted by Joe M 2012 2SS

I just got the rear pinion bearing and crush sleeve in last Friday. Also went ahead and ordered a transmission dipstick from Janetty.

I went by his shop today, he has an older Ford (1940ish), a corvette, and a gasser race car on his three lifts. Said probably next week.

He said he may be able to adjust the gear to get rid of the whine, but since I've drained the diff fluid twice and no metal shavings were present either time, he said there is a strong possibility that the gear whine is coming from the gear not being machined properly. Motive will blame it on the previous install even if it is in right, so I'm out the $$ for that gear. Wont ever buy anything from them again.

I could take a chance on buying another gear, or just put the factory 3.27 back in that came out. He recommends doing the latter since that gear never had any issues.

He has a ton of experience with GM differentials, so I'm going to let him do what he thinks is best.

I know I told you that you could have the old gear, and the posi unit, but at the time I did not know I would have all this trouble with the brand new Motive gear, so if he wants to put the 3.27 back in, I'm going to have to do that.

You can still have the posi unit, as I have the true trac in now. But if he wants to put the original gear back in, then I'll have to go that route.

I hope you understand.

Oh I understand for sure, just hope you get fixed up so you can run with that new tru trac.

[Joe M 2012 2SS]

Originally Posted by WoodBoss

Oh I understand for sure, just hope you get fixed up so you can run with that new tru trac.

The True Trac is fine and works great.

I've drained the diff fluid twice, no metal shavings at all, oil is clean, but the gear whines a good bit at 35mph +.

I wish I had never got the Motive 3.91 gear, and just had the True Trac done. The gear was put in since the old one was going to have to be removed anyway, in hopes of gaining a couple tenths. $300 wasted instead.

[WoodBoss]

Why don't you run it and see what it does before you remove the 3.91s. If it's quicker than the 3.27s you may reconsider going back?

[Joe M 2012 2SS]

Originally Posted by WoodBoss

Why don't you run it and see what it does before you remove the 3.91s. If it's quicker than the 3.27s you may reconsider going back?

The gear whine gives me a headache after a 15 minute ride, it's 20 minutes to Shadyside.

I'm driving as little as possible now, because I don't know if the gear will fail or not.

I'm sure it's quicker, but doubt I will do this again. I'd rather be slower, and not have a headache every time I have to drive 15 minutes or more.

[saluki]

why not put some AAM 3.91's in it?

[WoodBoss]

You should run it at least you would know if it would be worth putting another set of 3.91s in it.

[Joe M 2012 2SS]

Originally Posted by WoodBoss

You should run it at least you would know if it would be worth putting another set of 3.91s in it.

I don't know if it will break if I take it to Shadyside and make a pass, and don't want to risk it. Last thing I would want now is for the gear to break and damage the True Trac.

Originally Posted by saluki

why not put some AAM 3.91's in it?

Already wasted $300 for the Motive Gear, don't want to put any more money in another one. AAM has no guarantee their gears will not whine as well, I checked into it.

I know the factory gear will not whine, so I'd rather go with a sure thing than take another chance.

[WoodBoss]

Did you get fixed up Joe?

[Joe M 2012 2SS]

Supposed to go in the shop next Tuesday. Spent more money on an AAM 3.91 gear.

[frankwjr]

if your mechanic does his job right...the AAM's should be whisper quiet....make sure he knows they are 2 cut vs 5 cut....


if he has any q's...point him to this web site...http://www.demandaam.com/technical-s...ng-pinion-sets


this is what I used and after a shit load of street/hwy miles and several trips to the 1/4....don't even know I have a rear diff...shhhhhhhh


good luck man!


peace