NoGamesLS1

iTrader: (16)

I am tring to decide between a spool and a truetrac. The car is about 550rwhp and will have up to a 250 shot on top of it. The car is my DD. It wont see the track that much, probally less than 5-6 times a year. It will probally only have a drag radial, but there is a possibility of running a slick. Will the truetrac last? How does a spool drive on the street? What about some sort of electronic/air locker? I have ruled out a detroit locker since they are unpredictable.
Thanks
Steve

one2run

iTrader: (5)

I bought the TruTrac and love it. I had concerns about it being a spool at first (long story) but after I had realized (from reading the intructions) that this was in its design, I am happy with my choice. The draw back is it only comes in a 31 spline axle.
You are throwing down way more HP and TRQ than I am. Bob @ EPP, who I had bought mine from, says that if you are looking to build a car to run consistantly in the 10's, go with the spool & 35 spline axles--sucker will not break.
If I had your cars power, I would have went spool.

EPP

iTrader: (22)

I'd go with a spool. I've driven a Trans-Am and a Camaro with spools on trips, one was in the rain, without any annoying problems. You'll never outgrow a spool. Bob

02NBMWS6

iTrader: (22)

how much power would you say the tru trac could safely handle?

John35thSS

Do a search on my user name I still have photos posted on what happens with 656rwhp and 581rwtq with a truetrac in a 6 speed car.

If you dont mind losing abs run a spool, or even better keep it all and run an s60 with the 4 pinion beast of a posi stange has.

John

chicane

Well... since its a DD and your only going to see the strip 5-6 times a year... that would rule out my recommendation for a spool.

I have installed ARB's and ELocker's in street chassis'... but the ARB is too labor intensive for its required maintenance (it tends to eat up 'umbrella' seals with daily use and normal lubericants). The ELocker's are not too bad and dont have the internal seal issues that the ARB does... but I dont have enough feed back to give you a real impression one way or another. But it's so far so good from the related clients.

A TruTrac isnt a bad selection either. A 9" TrueTrac is different than that of the 12 bolt version. The 9" unit is stronger, so dont let the stories of the 12bolts unit be the reason you have turned away from it. But... it wouldnt be my first choice either.

Detroit lockers are not unpredictable and are not as bad as everone makes them out to be. Most everyone around here doesnt know how to drive them properly, either by just driving them like the normal idiots they are or because they were not informed on the finesse it takes to drive one on the street in a passenger car. And yes... you have to drive them a little differently. But if you are aware of those differences... its not that bad at all. Just learn and understand its mechanics and learn to pre-load the dovetails. I have been using one in my daily driver and have for the past 11 years without an issue. But whatever...

But as for a spool... there are related maintainence and drivability issues that most of you have not been informed of. And honestly Im not surprised, to say the least. There are few of us around these parts that actually build differentials... and there are plently of those around here who just pull things off a palet and install them. Frankly, I dont really expect them to tell you what you really need to know... because they themselves, dont know to begin with.

First of all in the maintainence catagory... you will need to take the differential apart at least one a year to check for axle twist, axle shaft and internal spool spline deformation (Moser axles are single point cut splines = their weakness) and to check the spool itself for cracks. This is true even if you never see a drag strip. Second in the drivability catagory... unless you never drive it in any kind of incliment weather, including light rain... the tire wear definately sucks. But then again, if you do like driving in the rain (I know how Nor Cal can be)... I hope you like driving sideways thru intersections... unless you like driving 15-20mph. And dont even think about getting into the throttle... unless you like to. I know I do. It is fun to say the least...

Then... there is always the DANA 60...

You choice is going to be driven by your axle selection (spline count wise). But if your choice is Moser... you better go big to compensate.

02NBMWS6

iTrader: (22)

so are you still driving on the cracked tru trac?

NoGamesLS1

iTrader: (16)

Wow that sucks. So no truetrac then... So if you go to a spool you loose abs and tcs? So how much can this s60 posi hold? I havent looked into that yet.

NoGamesLS1

iTrader: (16)

I have never driven a car with a locker, but someone I know has a bronco with one and he said he hates it because just after a shift the car will kickout in the rear. Is there a way to prevent this?

NoGamesLS1

iTrader: (16)

Is this what I should be looking for? With the posi? Thanks for the info! Do they make a 4 channel s60?

John35thSS

I bought a strange hd posi, was worried the metal from crack or the galling worm gears would damage the ring gear.

I havn't run the hd yet but I have several friends using them without issues.
I had to be the smart guy to try something new
John

John35thSS

S60 with 4 channel or 3 channel stock gm sensors, also you dont have to buy any crappy eaton or us gear product you can get the monster power lock posi.

If I had to do it again s60 powerlock and I wouldn't have my triplet 12 bolt posi party.
John

chicane

Biggest difference here is... the center of gravity and wheel base. Kicking out the rear is resultant of them both. Passgner cars are much different.

John summed up your other question.

EPP

iTrader: (22)

I wouldn't push it past 600 rwhp. Bob

BlackScreaminMachine

iTrader: (17)

If you havent read my post, on my Moser 12 bolt set up by Moser, 3.42 gears, 3800 race weight, 35X rwhp 36X rwtq, I broke my Tru Trac. It was due to wheel hop, not launch but just saying it can be broken.

A spool is not crazy on the street but you will know its back there.

John35thSS

Do you have any photos of your broken trutrac yet, just wondering if its the same failure as mine.

John

BlackScreaminMachine

iTrader: (17)

Car is going to the shop next week, Ill have them give me the unit. I hope I can have something to share. I also found out with Moser 12 bolts, if it came with the tru trac, you need to use another one, the axles are cut at a different angle. But I was told the unit is an upgraded unit.....

2 fast 2000

iTrader: (4)

I have a S60 with a spool in it. I would not recomend a spool for everyday driving! I don't even drive my car everyday and allready it's getting annoying. I'm going to be switching to a different set up in my S60 in a little while. The spool will tear up your tires and it is hell to get into tight spots or parking spaces.IMO!

John35thSS

So did you have to buy another trutrac unit or did eaton give you a free replacement.
If not I'd be looking to buy another set of axles so I wouldn't have to buy another trutrac.
Is it possible you can use a strange diff if your axles are cut at a 45 degree pressure angle.

John

BlackScreaminMachine

iTrader: (17)

Im buying another unit, my original was out of warrentee, I will still have the broken one, and I can try to barter with them. A lil R&D for reimbusement.