I'm running a 9 inch Trac loc with 4.30 gears in my 27 and I abuse it regularly. No problems whatsoever and both tires hook exactly the same. It also acts like a one wheeler on turns with no funny handling characteristics. Don
Once you're in the corner, though (and as long as you can stay on the gas and keep it locked!) with the locker your steady-state condition is a spool. I can't say I've ever driven a locker and a DPI/Torsen/Truetrac in an apples-to-apples situation on track, but to me the gear diffs generally feel 'loose' but very progressive, no abrupt transitions.
Only during neutral torque applications, When you stomp it, the inside wheel is the most likely to spin. With a Detroit , the inside wheel catches up to the outside wheel and locks. In road racing the slip angle of the tyres is greater than the differential speed, so it doesn't make any difference over a spool or detroit. If the "Roll Couple" [Fr & Rr Roll stiffness ] is set up correctly a spool doesn't cause corner entry understeer. Many racers blame the spool and use a Detroit as a "Band-Aid"
I had a Yukon Grizzly Locker in my pro street and loved it, I burned up a traditional "posi" I'd never run anything but a locker in H.P. applications again. It was very streetable, never had a bit of trouble.
have been running detroits on the street for years...not as noticable with a auto trans.might hear them ratchet in parking lots...every now and then when going from reverse to drive ,coming out of a parking spot they will make a lite "POP"... but its not bad...like all things in old cars,,its something you get use to and learn to drive/life with...
Blowby , I have been running a powertrax in my 8" for 11 years/35K miles , absolutely no troubles... FYI, the 8" & 9" ford use the same unit [as long as the axle splines are the same].. slight mod. of the cross shaft is req'd for 8"... has to be shortened .030 [grinder] ....real simple... dave
I had a locker in a 69 Boss. Kool factor from hell, and the only thing that got my attention was when it would end up in the "high side" of the ratcheting system after a turn. If I applied some weight to the loud pedal it would snap really loud. The 1st time it happened I pulled over thinking I broke something. I got used to it. That car put a major ass whipping on a 289 Sunbeam with Webers, TWICE! Once from a roll and again from a dead stop so power was there, and that diff is still in that car some 29yrs later. I can't raise my right hand as to how it's current owner treats it but treated it to what it was built for. I miss that car...
Useless when unlocked. Difficult steering, and vicious tire wear if left locked. Extra equipment to install and maintain. Where is this best you speak of?
Yeah, read some not too good things about them here: http://www.angelfire.com/my/fastcar/diffey.html Too bad, found one for 300 bucks.
I installed one of these buggers in a Ford 8" rear about five years ago... Serious pain in the ass. Did the straight installation as directed by the instructions. Installed in the car and noticed right away that the "clutches" would slip past each other and you could push the car even when in park. Putting power to it worked about as well as expected, lots of clanking but no drive. I pulled it apart and started measuring things, I figured I needed some shims behind the "spider gear" on each side to get them to engage properly. My customers differential housing might have been worn causing this but it took about three attempts to get the shims the proper size for everything to work. My former partner had called Powertrax with mixed results. I didn't get a satisfactory answer as to why we had to do what we did. We installed an Auburn Diff in that car the very next week.
You see these things in rock crawlers and the like where the off-road guys want a diff that locks and stays locked, Truetracs don't like having a wheel dangle out into space then hit a rock and bite, unless you preload it by riding the brakes it apparently tends to break them. But road and off-road are very different uses for a diff. Maybe might be okay for a drag car, don't know. For a road-course car you might as well run a spool, you don't want the extra hardware hanging around. And for a street car it's worse than useless.
^^agreed^^ I have both the Detroit and ARB in a jeep. The Detroit does have the snaps and creaks but is tough and drive able even with that short wheelbase. You get used to it and won't notice after awhile its quirks. As said before the first time it comes down off a tooth you will think what broke? Also freaks out your passengers. Posted from the TJJ App for iPhone & iPad
ARB Air lockers are good for cheating in open diff classes When you get put over the rollers you can unlock them. Did I mention the word "Cheating" , I actually meant "Innovation"
Good thread. I didnt think i was going to need the info just yet, but managed to blow the trac-lock apart in my deuce today leaving work. I'll pull it apart tomorrow and see how bad. Lol Guess the blower motor 5 speed and cheater slicks were too much for it. Thanks for the info Tony
What I've withnessed..Trac-Loc can handle an extreme amount of abuse but the biggest hurt is when the "foot" stays in it when there too much "bias" in traction..In wet weather/snow you can feel the unit searching for traction side to side and is fine under lite load but if the "foot" goes in it then one wheel will run away, this was engineered in by Ford so the one wheel that was at road speed would steer the vehicle..So if the "foot" stays in it long enough will cook the clutches, got to know when to abuse...At the races it can be forgiving for not haveing suspension set and won't hook [left/right] bad but won't last if you don't get the suspension dialed in.. Detriot Locker...Neet unit, locs with throttle and don't give a turd about traction..Drove home from the drags twice with a broken axle, so saved my butt,,A little weird with real one wheel drive but a little extra turn in the steering wheel would compensate..Most important thing at the drags is to do a little aggressive clutch at very little throttle to make it loc under lite load and do burn out with out making any turns inbetween, besure to make some mild starts to get suspension adjusted for equal traction or you will take a rite or left..Yes very noisy but mostly at first throttle away from stop lite, ect..I can't ever remember it making noise at speed [highways] in turns...I ran it for about six years on the street and drags with 5.14 gear...
OK, dump question of the day: How do you know if an 8" has factory trac loc? I don't have axles to poke into this swap meet pumpkin I got here.
This concerns 9" but the code should still work if you have the OE tag. http://www.kevinstang.com/Ninecase.htm If I recall, most of the plate style diffs have pocket recesses with a thick cover. The heads of the ring gear bolts will also be smaller.
Thanks ELpolacko. This one I have is open then. Sounds like the one you mentioned, Truetrac, is my best bet.
Since you guys know lockers, what could you tell me about this one? I recall buying it 10 years, for 31 spline. I'm trying to de-clutter. I know the other one is a 31 spine spool also for a 9": [/QUOTE]
The Jalopy Journal
