I was at the track last Friday and my last run of the night didn't go so well. I got a hellacious launch off (been hitting the 1.5's lately) but the next thing I know I am hearing and feeling banging sounds from the drivetrain. I eventually lost all ability to put power to the ground and stopped 1/2 way down the track - suck! Well, I got towed off the track and home and pushed the car into the garage. I knew what had probably happened when I got under the car and turned the driveshaft - which turned easily without any resistance other than one tight spot. Anyway, I took the cover off and this is what I saw:
(http://i43.photobucket.com/albums/e360/Domeskull/DSCF1763.jpg)
This is an Eaton E-Locker that uses pins to lock the spyder gear on the ring gear side of the differential to the case so it can't rotate. I figured the gear on the axle that had the pins in it's backside had broken, but it was actually the two side gears that let go. At least the axles were protected from the junk, but the pinion gear has a little bit of damage to one of the teeth that hit this piece of spyder gear that got wedged between the ring gear and differential case. I'm not sure what can be salvaged here and I've sent an email to Eaton to see if they have improved the side gears strength in the repair kit, so far just a generic response. Here is the gear piece wedged between ring gear and case:
(http://i43.photobucket.com/albums/e360/Domeskull/DSCF1764.jpg)
That's an 8.8 right? If so time for a 9 inch lol.
Just time for a differential that doesn't have parts that break when a little force is applied. I'm going to see what Eaton says.
How much power is that differential rated for? Were your running slicks or drag radials when it broke?
Drag radials. Eaton doesn't rate their differentials that I can find, but a differential vendor gave it his highest rating for drag racing so I figured it would be good for normal driving and drag racing too. The "spool on demand" part was cool, but breaking side gears is not cool :(
No it's not:hick: How much power does your engine put out to the rear wheels? Perhaps the breakage *could* be because of the weight of your car vs a Mustang. The *race weight* of mine with me and 1/2 tank of gas is 3750 lbs:punchballs: (and I weigh 160 lbs).
A little force hahahahahahahah,you funny.
You gots alota force.
I'm putting about 450/400 to the wheels best I can tell. Believe it or not, they had the scale open at the track on Friday and I was significantly shocked that the things I have done over the years to minimize weight had lowered the car weight from 3700lb without KB to 3550 with KB - both times at 1/2 tank and I still weight the same 170 lb. I dunno why this thing broke - I know I was shocking the rear on launch, but this may just not be a good design for the track - I'm the only person I know using this for racing, so perhaps even Eaton doesn't know if it's capable at the track.
1.5's........ That is a quick pouncing cat off the line. No wonder.
Spider gears FTL.
ouch that does'nt look good at all..what spline differential is it?
i twisted my 28 spline axles and diff big time back in the day.. i went with the F150 31 spline differential and moser axles about 6 years ago..
i felt at the time it was the safest route..
i felt i could'nt trust the auburn differential i seen to meny explode and they can't be rebuilt. which would be $400.00 out the window or out the rearend sort of speak..and thats why i went with the F150 differential at that time i never looked into the eaton differential.
i'm only asking questions because it seems these days my opinion is'nt worth much on this forum..
Nick
I cant imagine anything but the opposite. I thnk i saved some data you put up on the f150 info, good stuff.
Yep, first loss at the track this year. I've smoked Corvettes, Camaros & all that rice. Heck, I beat a friggin' ricer in one race where I almost hit the wall as I got sideways off the line and crossed the finish line @ 73 MPH. I won by 7/10ths!! LOL!
Good questions. It's a 31 spline Eaton E-Locker. If you look at the pictures, you'll see that the spyder gears attached to the axles were undamaged!! It was the side spyder gears that connect the force from the driven ring gear to the drivers side axle that broke. The passenger side spyder gear is the one that has the pins go into it's back when it's locked.
I wanted an open differential for the street (advantage on an electronic locker) because the torque of the KB makes the car dangerous to drive on the street. If only one wheel can spin, it helps keep the rear planted in turns when I get on it. Believe me, I've spun cars repeatedly in my life when both rear tires spun when I got on it - I HATE doing 360's on the street!
That sounds SO much like my first run in the Mustang it's scary!!! :hick:
Did I miss something?
Well, I picked up a truetrac differential and I figured I nab a set of 3.55's as I was getting tired of the 3.73's, so I should be good for a while after this.
I thought Torsens and Truetracs didn't hold up well to shock loads.
i know a guy with a true trac in his trans am thats putting down about 450-500hp to the wheels.hes launch that thing pretty hard on nittos and the truetrac lives.
Once the clutches go out in my tc, I will be putting in a trutrac. I have one in my truck(9") but the truck puts down 550+hp, 600+tq at the rear wheels and weighs 5200# and pulls 1.8 60' and I love it on the street. One guy on 460ford.com said that those diff's were rated at around 750hp, but he runs a 70 torino running mid to low 9's with the trutrac and pulls the front wheels a foot off the ground
I got this info from Eaton when they finally got back to me about my broken E-Locker:
I also read of a 9 second Lighting running one of these. Ever since they switched to the 3 pinion design on the Trutrac, it's been a solid track differential based on my research.