Eaton Posi Group Buy

[maraudernkc]

I am looking at putting together a group buy on either Auburn and or Eaton Posi untis. Are stock units will not hold up to the power we are throwing at them.

What I need to know is the following:

Who would be interested if the price was right on the Posi Unit?

What brand would you want?

Would you want 28 spline or 31 spline? (same price)

Who would want axles?

Let me know and I will post pricing later in the Week.

Thanks, Greg

[MarauderMark]

This is a great idea as many will need it if they're going over 450 hp
as i found out the hard way.But the g/b is a little to late for me.

[merc]

This is a great idea as many will need it if they're going over 450 hp
as i found out the hard way.But the g/b is a little to late for me.

MarauderMark is the Captial Area Marauder group official R&D specialist. :lol:

[RoyLPita]

Greg, aive Tmac1337 a PM about this. He was asking me about the 31 spline Eaton and possibly axles, too.

[Cobra25]

If the price is right I have a interest. I would want the Eaton Posi unit. 28 or 31 Spline? What # spline is in their now ? Axles,no.

[maraudernkc]

Our stock Marauders have 28 spline axles.


If the price is right I have a interest. I would want the Eaton Posi unit. 28 or 31 Spline? What # spline is in their now ? Axles,no.

[Cobra25]

Our stock Marauders have 28 spline axles.Could I use the existing spline (28) or should it be changed when the Eaton is installed? The car has 19500 miles on it if that has to be taken into the equation. Also would I need a 8.8 pinion installation kit also?

[O's Fan Rich]

Funny... I was just thinking about this.

I'd wanna go 31 spline. Do not know which diff is better.
But, I'd be in as long as it is a good deal.

[MI2QWK4U]

If you can a good buy on the Eaton, do it. Its a solid unit. If you upgrade to a 31 spline Eaton, then you will need to upgrade to the 31 spline axels too. I would be interested in a 31 spline Eaton and the 31 spline axels as well. Who do you have in mind to do the axels? I was under the impression that an existing axel needs to be modified somehow to work on the marauder. Let us know, but im very interested.

[MikesMerc]

If anyone intends on spending money to get the rear end upgraded, I strongly recommend the Eaton unit, and to go with 31 spline. Yes, you need to do the axles too, but your getting to get more "beefing up" per dollar spent that way than just spending money for the upgraded 28 spline differential.

I understand the Moser now makes a 31 spline axles. This may or may not be true. When I upgraded no one made a 31 spline axle that fit the Marauder so I went with a custom pair.

Good Luck guys. This is an awesome group by idea.

[Cobra25]

Are the 31 spline axles from Moser a direct fit or do they have to be machined or shaved? Also it might be a good idea to put in a new set of carrier bearings too.

[MarauderMark]

Are the 31 spline axles from Moser a direct fit or do they have to be machined or shaved? Also it might be a good idea to put in a new set of carrier bearings too.
When i was getting my Eaton unit They had in stock with 28 spline axles.if i wanted 31 spline i wouldv'e had to wait 2 weeks as they concider them custom order for our cars.Thats what i was told.Replace everything except ring and pinion.Also had a problem using synthetic oil in the rear had to take it out and use regular gear oil.

[Cobra25]

When i was getting my Eaton unit They had in stock with 28 spline axles.if i wanted 31 spline i wouldv'e had to wait 2 weeks as they concider them custom order for our cars.Thats what i was told.Replace everything except ring and pinion.Also had a problem using synthetic oil in the rear had to take it out and use regular gear oil. What problem did you have with the Synthetic gear oil ?

[TooManyFords]

I'd be interested in the E-Locker from Eaton... Either 28 spline is fine. 31 if the replacement axles are not too much.

Cheers!

john

[HwyCruiser]

I'm in. I've got a few questions for our mechanics out there though:

- Is upgrading to the 31 spline axles a bulletproofing measure or are we starting to see people tearing up the 28 spline axles (not counting the soft axles covered under the TSB)?

- Just thinking of the budget minded here, but how much additional labor does swapping the axles take or is this "while you're in there" kinda thing?

- Is replacing the diff / axles something that someone that does routine maintenance can do (special tools required, etc.)?

[carfixer]

What problem did you have with the Synthetic gear oil ?
Eaton specifies that non synthetic fluid be used with their posi unit. I believe it has to do with the friction material they use.

[Rider90]

Eaton specifies that non synthetic fluid be used with their posi unit. I believe it has to do with the friction material they use.
What do you guys suggest for rear end fluid?

[Cobra25]

Eaton specifies that non synthetic fluid be used with their posi unit. I believe it has to do with the friction material they use. Thank you for letting us know.

[Tallboy]

What do you guys suggest for rear end fluid?

I've got NAPA 80W90 mineral gear oil in mine, with the Eaton 28 spline set-up.

[Cobra25]

I've got NAPA 80W90 mineral gear oil in mine, with the Eaton 28 spline set-up. Any reason you use that oil instead of the stock oil from Ford.

[Tallboy]

Any reason you use that oil instead of the stock oil from Ford.

Yeah, Z. When I got the Eaton Posi, there's a little letter inside that says the following:

"It is strongly recommended the Eaton Posi LSD you have purchased be installed using a Mineral Based 80W90 Gear Oil and a 4 ounce bottle of Limited Slip Additive. The Eaton Posi is not recommended to be used with synthetic gear oils."

So, I got some gear oil from NAPA, and stole a bottle of LSD additive from Carfixer's tool box.:D

[Rider90]

I started a new thread looking for non-eaton advice...


for now ;)

[Cobra25]

Yeah, Z. When I got the Eaton Posi, there's a little letter inside that says the following:

"It is strongly recommended the Eaton Posi LSD you have purchased be installed using a Mineral Based 80W90 Gear Oil and a 4 ounce bottle of Limited Slip Additive. The Eaton Posi is not recommended to be used with synthetic gear oils."

So, I got some gear oil from NAPA, and stole a bottle of LSD additive from Carfixer's tool box.:D So the stock rear oil from ford is not mineral based or 80W90. Understood, thanks for the info. Chuck.

[Tallboy]

So the stock rear oil from ford is not mineral based or 80W90. Understood, thanks for the info. Chuck.

Actually, I think it is. When Carfixer did the axle TSB, it came with the synthetic gear oil. Of course, I promptly smoked the stock Traction-Loc unit drag racing.:)

[Tallboy]

Here's a link to the Eaton Posi LSD unit. It's a pretty informative site. Lots of good stuff to read here...

http://www.traction.eaton.com/prod3.htm

[Cobra25]

Here's a link to the Eaton Posi LSD unit. It's a pretty informative site. Lots of good stuff to read here...

http://www.traction.eaton.com/prod3.htm Thank you, I will read it.

[MarauderMark]

Eaton specifies that non synthetic fluid be used with their posi unit. I believe it has to do with the friction material they use.
Thank you .Thats exactly what happened too.Sorry i didnt answer sooner Zoltan.

[MarauderTJA]

I would be interested in the Eaton unit with 31 spline as well as axles.

[King Fubar]

I'm in if the price is right

[Cobra25]

I'd be interested in getting a price when you can on the Eaton 31 Spline unit with axels & the Eaton 28 spline with out. A complete kit.

[tmac1337]

Count me in as well. I will take either the 28 spline posi unit or the 31 spline posi unit with axles if that is offered as a package.

[MikesMerc]

- Is upgrading to the 31 spline axles a bulletproofing measure or are we starting to see people tearing up the 28 spline axles (not counting the soft axles covered under the TSB)?




I've seen a few sets of broken axles now. If your going to spend the money, do it right and get the 31 spline diff and axles. Upgrading to the Eaton (or Auburn) 28 spline diff isn't a bad thing....you'll still get a much better limited slip unit that will withstand more power and the rigors of drag racing. But, do be aware that the 28 spline axles can, and do, break.

[Zack]

If you dont have wheel hop, it is highly unlikely the axles will break.
Just my opinion.

[HwyCruiser]

Is the only thing extra required for an axle swap new bearings?

I've been reading up some on the net and it doesn't seem like a differential swap is a novice job because you still have to dial in the gear backlash. I might as well go for the 4:30's that I should have done the fist time while I'm at it. This isn't looking cheap.

[SergntMac]

Sorry...I lost my place.

[merc]

Auburn Fan here :grad: 1.993 60 foot times on O.E.M shoes

[HwyCruiser]

Sorry...I lost my place.

Mac, that was good info. Greg was asking for feedback on all options.

Here's a question from the cheap seats... is the OEM limited slip so crappy it's not even worth rebuilding?

[maraudernkc]

Below is a link that has some great reading on the diffrent types and brands of posi units.

http://ringpinion.com/content/technicalhelp/default.asp?pid=128


Info on Bearings needed. This does not include if you do the axles.
http://ringpinion.com/content/technicalhelp/default.asp?pid=139

[MikesMerc]

If you dont have wheel hop, it is highly unlikely the axles will break.


Just FYI, I've seen two broken axles without any wheel hop at all.

450hp + 4300lbs + sticky tires + aggressive launches = broken axles over time.

I'm not suggesting a spline change for the casual runner.

[maraudernkc]

JD, I don't think it's crappy but it's was not designed to handle the kind of HP that you are laying down. Hell a stock Maraudrer can't even spin it's rear tires unless your on ice.


Mac, that was good info. Greg was asking for feedback on all options.

Here's a question from the cheap seats... is the OEM limited slip so crappy it's not even worth rebuilding?

[HwyCruiser]

http://www.moserengineering.com/moser_interior/axletech.htm

If I'm using this calculator right, they recommend a 31 spline at about 570 rwtq (2.84 1st gear ratio with 4.10 rearend gears). Although they don't list a 28 spline, eyeballing their chart would put the rating of a 28 spline right about 400 rwtq with 4.10's??!! They do say that there is about a 200% safety factor built in though.

[CRUZTAKER]

I will be watching to see what the final group buy will be.

Not being in the over 400hp group, I would like to add that I tore up my OEM LSD in a very short time once I found tires that actually hook.

I went with an Auburn 28 as a replacement because Eaton was back ordered too far out to suit my immediate needs at the time.

I have already noticed, since the NOS addition, that the Auburn is slipping as well after two summers.

I personally would like to see what you guys get for us in a nice Eaton 31 with axles.;)

[DEFYANT]

Subscribing with interest.........

[BUCKWHEAT]

From the sounds coming from my 39k rear end, sign me up.

[tmac1337]

I would also like to see a pepperoni pizza with extra cheese included as well!

Also Ford Racing sells a posi bearing/pinion installation kit on their website for $120.00. Complete rebuild.

[Kelly]

Same here,car born 8/02 TSB time frame.



Subscribing with interest.........

[DarthMarauder]

Is the only thing extra required for an axle swap new bearings?

I've been reading up some on the net and it doesn't seem like a differential swap is a novice job because you still have to dial in the gear backlash. I might as well go for the 4:30's that I should have done the fist time while I'm at it. This isn't looking cheap.

I not completely sure but when you do a diff change isnt the pinion gear still already set so all you have to do is reshim the diff by checking heel and toe and reshim till you have it center. Then you are pretty much set. Someone please verify or tell me i'm bull :bs: cause this is my thinking that way I know before I take on a project like this????

[MarauderTJA]

If you dont have wheel hop, it is highly unlikely the axles will break.
Just my opinion.

Your right Zack, except if you decide to use slicks...

[Zack]

Your right Zack, except if you decide to use slicks...

Heres some info on my car.
I had the axles replaced via TSB from Ford at around 5000 miles.
I had the 4:10's put in along with the stud kit and girdle at about 2000 miles. The control arms went on at around 9-10K miles.
At 21000 miles, i had the eaton 28 spline installed for good measure.
My stock diff had no signs of wear, fatigue or anything out of the ordinary.
I would bet money that the combination of the studs and girdle, control arms and the tsb axles all installed at such a low mileage will guarantee I will NEVER break an axle.
We shall see....

[MarauderTJA]

Heres some info on my car.
I had the axles replaced via TSB from Ford at around 5000 miles.
I had the 4:10's put in along with the stud kit and girdle at about 2000 miles. The control arms went on at around 9-10K miles.
At 21000 miles, i had the eaton 28 spline installed for good measure.
My stock diff had no signs of wear, fatigue or anything out of the ordinary.
I would bet money that the combination of the studs and girdle, control arms and the tsb axles all installed at such a low mileage will guarantee I will NEVER break an axle.
We shall see....

Good info. Have you only used drag radials or have you used slicks?