transmission??

[blackbird77]

I have a 2000 Trans Am with the orginal 4l60E(junk). i have heard of guys swaping out for a th400,and was wondering if this a direct bolt up or if there is any fab work or swap kit needed?? I have had the 4l60 out and "built" 3 times i cant seem to keep it in the car. Im only running around 475-500hp and was told that the 4l60 could handle that....seems not......im also running a very large converter (4400) that i want to replace too..(too big for the street). If anyone has any sugestions i would appreciate it as i have not been able to enjoy my baby in 3 years due to the time i have needed to save enough money to pull the tranny each time and fix it.........thanks to all

[Guest432]

I have a 2000 Trans Am with the orginal 4l60E(junk). i have heard of guys swaping out for a th400,and was wondering if this a direct bolt up or if there is any fab work or swap kit needed?? I have had the 4l60 out and "built" 3 times i cant seem to keep it in the car. Im only running around 475-500hp and was told that the 4l60 could handle that....seems not......im also running a very large converter (4400) that i want to replace too..(too big for the street). If anyone has any sugestions i would appreciate it as i have not been able to enjoy my baby in 3 years due to the time i have needed to save enough money to pull the tranny each time and fix it.........thanks to all

That sounds way off, who built your transmissions? I built my own 700r for the formy (it is, for all practical purposes, a 4l60e minus the electrical controls, and a few differences in the hsg) and that motor was running a lot more power than you are, to a set of slicks out back no less (at lapeer and etown, both of which hook on spit) and never had any problems. The th400r4 vs 4l60e is not a direct swap, and you will need to make some modifications or build an adapter plate, but that 4l60 should, with a little work, easily hold over 500hp (I know a guy running one, lives a couple miles from me, with a lsx motor, supercharged @ 12psi, bottle, heads/cam, and stroker, which I'm assuming is WAY more than you are running) and he's running a built 4l60e and hasn't had any problems.

Also, where are you located? If I know anyone out that way I'll give 'em a call, see if I can't find a better shop for you, as you shouldn't be having any problems at all (the 4l60e outta the box won't hold the kind of power the t56 will, but with a little work, it should; and the T56's were rated for at least 450-500hp if memory serves). Sounds like your converter is WAY too big, also ... I'd say 3000 tops, 4400 is roughly where my friend is running in his '64 falcon, and he's running 8.0's @ 1/4 on motor and small block! I'm guessing, with 450-500, you're nowhere near those kind of times. My other guess is maybe the converter is too big, and the sudden torque being applied to the transmission is just ripping it apart? Just trust me, though, you don't need any more than a 3000rpm stall converter to get that thing off the line fast, and all you're doing is making what should be a very street-able car into something that's just unmanagable (I can't imagine having a 4400rpm converter in a car here in WV with the mountains ... dear god!)

Hope that helps!
- JR

[rkuelbs]

We've built quite a few 4L60E's and 700R4's around here (I've liked all my own drag cars to be streetable, so I've always built 700R4's to get that OD on the highway).

Our usual recipe for the ones we build......I would look for all of this in any one you have built. Should be good for 650-700hp. Can do 750+ with cryo treatment and a "beast" sun shell instead.

New (late design) front pump seal, Teflon bushing, 10-vane pump rotor assembly, Trans-Go Hi-Rev steel rings & priming spring, Trans-Go HD pressure regulator spring and bumper spring, Trans-Go .532/.500 boost valve, rotor to pump clearance set at .0015"-.002", and new stator support.

A reworked or new reverse/input drum, along with the Turbulator low-drag steels and Borg Warner clutches. The Belville spring is replaced with a waved spring to eliminate the belville from eating the drum.

The stock input drum can hold 575 to 600 HP. I add a steel sleeve and remachine the overrun piston to prevent splitting the drum open from high loads, which should be good to 700hp. New design 29 element input sprag, Borg Warner clutches for the overrun and late design Borg Warner forward clutch assemblies, Borg Warner Hi-Energy clutches along with Kolene steels used in the 3-4 clutch pack, Trans-Go Hi-Rev springs replace the OEM 3-4 and forward springs and 3-4 helper springs (the stock spring will allow centrifugal apply around 5000 and burn your 3-4 clutches, the Trans-go springs are good to about 7800 rpm), clearance for the 3-4 clutch pack .025" -.035".

New or carefully examined input sun gear, forward planet with bat-wing thrust washers, input internal gear, reaction carrier shaft with "roller" bearing instead of metal thrust washer, a new GM heat-treated sun shell (again, a "Beast" sun shell for over 700hp, but the GM Heat Treated version is lighter, and recommended for 550-650hp), the latest design Borg Warner low/reverse roller assembly. Turbulator low-drag steels, Borg Warner clutches, new or carefully inspected rear planet, reaction sun gear, internal reaction gear, and internal reaction gear support, a bronze rear case bushing, Teflon extension housing bushing, and a Vamac rear seal.

Borg Warner Hi-Energy 2-4 band, new Corvette 2nd gear apply servo used with Viton seals. An additional spring is added to the cushion side of the servo to help provide a smoother 1-2 apply at light throttle while still allowing a firm WOT shift.

I use the "Modified" Trans-Go Performance Shift kit in conjunction with the large boost valve, Corvette servo, and the 9 clutch 3-4 pack. (This setup has proven to be the most reliable). I work with the accumulators to give the best possible part throttle shifts, and progressively firmer shifts with more throttle opening. Accumulator and governor tuning should be done in the car to achieve the best shift quality and timing for your application.

Also, a HUGE note.......call a professional Torque Convertor builder, and give them all the info on your car. If you give them all the details of exactly what's in it, and what you're doing with it, they should be able to build a convertor for you to give you exactly what you want. I NEVER recommend an off-the-shelf convertor for anything more than a street car that wants an additional few hundred RPM of stall speed. A custom convertor can be built for close to the price, that will perform at least 10x better in your car.

[Guest432]

We've built quite a few 4L60E's and 700R4's around here (I've liked all my own drag cars to be streetable, so I've always built 700R4's to get that OD on the highway).

Our usual recipe for the ones we build......I would look for all of this in any one you have built. Should be good for 650-700hp. Can do 750+ with cryo treatment and a "beast" sun shell instead.

New (late design) front pump seal, Teflon bushing, 10-vane pump rotor assembly, Trans-Go Hi-Rev steel rings & priming spring, Trans-Go HD pressure regulator spring and bumper spring, Trans-Go .532/.500 boost valve, rotor to pump clearance set at .0015"-.002", and new stator support.

A reworked or new reverse/input drum, along with the Turbulator low-drag steels and Borg Warner clutches. The Belville spring is replaced with a waved spring to eliminate the belville from eating the drum.

The stock input drum can hold 575 to 600 HP. I add a steel sleeve and remachine the overrun piston to prevent splitting the drum open from high loads, which should be good to 700hp. New design 29 element input sprag, Borg Warner clutches for the overrun and late design Borg Warner forward clutch assemblies, Borg Warner Hi-Energy clutches along with Kolene steels used in the 3-4 clutch pack, Trans-Go Hi-Rev springs replace the OEM 3-4 and forward springs and 3-4 helper springs (the stock spring will allow centrifugal apply around 5000 and burn your 3-4 clutches, the Trans-go springs are good to about 7800 rpm), clearance for the 3-4 clutch pack .025" -.035".

New or carefully examined input sun gear, forward planet with bat-wing thrust washers, input internal gear, reaction carrier shaft with "roller" bearing instead of metal thrust washer, a new GM heat-treated sun shell (again, a "Beast" sun shell for over 700hp, but the GM Heat Treated version is lighter, and recommended for 550-650hp), the latest design Borg Warner low/reverse roller assembly. Turbulator low-drag steels, Borg Warner clutches, new or carefully inspected rear planet, reaction sun gear, internal reaction gear, and internal reaction gear support, a bronze rear case bushing, Teflon extension housing bushing, and a Vamac rear seal.

Borg Warner Hi-Energy 2-4 band, new Corvette 2nd gear apply servo used with Viton seals. An additional spring is added to the cushion side of the servo to help provide a smoother 1-2 apply at light throttle while still allowing a firm WOT shift.

I use the "Modified" Trans-Go Performance Shift kit in conjunction with the large boost valve, Corvette servo, and the 9 clutch 3-4 pack. (This setup has proven to be the most reliable). I work with the accumulators to give the best possible part throttle shifts, and progressively firmer shifts with more throttle opening. Accumulator and governor tuning should be done in the car to achieve the best shift quality and timing for your application.

Also, a HUGE note.......call a professional Torque Convertor builder, and give them all the info on your car. If you give them all the details of exactly what's in it, and what you're doing with it, they should be able to build a convertor for you to give you exactly what you want. I NEVER recommend an off-the-shelf convertor for anything more than a street car that wants an additional few hundred RPM of stall speed. A custom convertor can be built for close to the price, that will perform at least 10x better in your car.

Nice to hear somebody actually knows what a BW tranny can hold! (worked for them for a while ... prototypes)

I think that's probably more'n what he needs, but yeah, there's no reason for any th700, th400, or 4l60, 4l80, etc. to not be able to hold 500hp with work in it. Even your muffler shops in Flint, Detroit, Saginaw, and Lapeer will easily build you a tranny that'll hold that kinda power (not that I'd bring a transmission to a muffler shop, but still) and if you're in the US, check out LS1Tech, just ask in your local forum for a good transmission shop. If you have problems, take it up with them first, but if they won't fix it, let them know you'll go back to LS1Tech and post it up, they're very serious on that site about making sure only quality shops advertise on there, and the loss of business should be bad enough for any quality shop to fix the problem and rebuild that tranny. But as myself and rkuelbs have said, there's no reason for a 4L60E to not take upwards of 600-700hp without problems if its built right.