Kyles 4T60E rebuild.

[1988GTU]

And when in doubt I just make the click click sound and say it's good... LMAO!

LawLerz

[woody90gtz]

I always torqued stuff before not to get any confusion, I just had a ftlb wrench that had a lesser low end range, so if you've ever used a 125ft/lb wrench to torque something to 20ftlbs you probably know what I mean, the click isn't so prominent so it's harder to ensure its RIGHT at 20ft/lbs.

And when in doubt I just make the click click sound and say it's good... LMAO!

Oh, somebody told me you didnt have one!

[3X00-Modified]

I'll add photos tomorrow.

Well, everything went good... Kyle and his paparazzi Ryan (Ryan took most of the photos this weekend, he stayed rather clean... LOL) showed up at around 8ish on Friday they grabbed something to eat and we ended up crashing at around 10... Up early at 8am to get started...

Started with just getting the old sucker out... Kyle and Ryan worked on that while I buttoned up his new trans.

Had the trans out by around noon time and stopped for lunch.

After lunch we headed to Advance for a filter kit, fluid, Oil pressure sending unit and new threaded coolant pipe adapter for the heater core... Found that leaking when taking the trans out. Also stopped at my parents house to pick up my fathers saws-all to get his old down pipe off his exhaust.

After a few issues with the new trans, the parking engagement rod being busted we got the whole thing in around 6ish, all buttoned up and sub frames in and ready to go... Just had to build a down pipe from there.

After Dinner we started on the pipe... I used a straight section and a 90* mandrel bend to replicate the 3100 down-pipe from 2 1/2 pipe. Welded it direct to the stock flange, That is apparently cast so that was fun to do...

In the end came out pretty good, slapped on his new dynomax cat (Nice cat I may get one for myself for $60) Put a 2 bolt flange where they had just welded the rear section to the down pipe and bolted it all up... Everything is nicely Tig welded

Took it for a ride and everything went well except for a nasty vibration... Found out the rotors had rust spots on the flange where it touches the bearing for each one of the three holes on the bearing, and we didn't put the rotors back to where they were exactly so they were wobbling... Fixed that flashed his ECU with a DHP 1.5 file slightly modded shift points for the 1:1 gearing, changed the sprocket ratio to prevent a SES light and removed his second O2 sensor code. He headed home around 1:30ish and made it there by 9:30 I believe... No complaints at this point in time so I'm guessing the ride was good, and no more slipping trans!

[woody90gtz]

Pics or it didn't happen...

[Rettax3]

Wow, um, I'll be putting in some white LED 194s I bought to compliment the front clear side-markers I got from Woody for the GTU... Now I feel like a wimp for the day... I might even get the driver's side window back in the track on the '97 Z-24, but still...

[turbotim59]

Hello, I have talked to you in the past about you trans mods and like this thread. Just as a reminder I am building a 96 Z26 Beretta as a NHRA stocker. Due to my involvement in a friends Pontiac Grand Am and his passing I ended up with the Pontiac and have been trying to race it as I can. It has a th125c and we have made several mods to it including changing the gear and chain ratios to 29 / 41 ( custom made gears ). Have you ever tried any such modification on a 4t60 ? That Gear change required a machined bearing hub that mounts to the case and relocating the retaining screws. Had to make a pilot to keep things lined up but it all worked well. I have been adjusting governor weights to get my shift points where I want them ( about 7000 rpm ). After I get it tuned in I plan to go back to the Beretta and the 4t60. The trans thats going in the car cam from a 97 chevy Lumina and has the best final drive gear set I can get. It is presently apart and calls to me every time I walk by. I did buy a rebuild kit and higher stall converter for it ( about 2500 rpm ). I would love to see some of your mods for the 4t60 and see if they would apply for a strickly drag build.

[3X00-Modified]

I've never had custom gears made but they are very similar to the 3t40, so whatever you did on that you would probably do near the same thing on the 4t60... Only problem I forsee is the driven sprocket being to large for the 4th gear hub... I don't know how similar this looks to the 3t40 setup, but there is a piston that has to apply 4th on the driven end where the 3t40 doesn't have that.



I would have to say my mods work pretty good for a drag setup I've gotten mine to shift really firm and quick consistently and no counter weight's to mess with... just reflash the ECM with a new RPM point. And it's still quite usable on the street... and I'm only at a 3.69 ratio which I think is high enough for the power that I'm making... any more gear and I'll just be spinning tire and fighting with traction more.

[3X00-Modified]

Ok Kyles pics now...

Subframes out!



Just the start of it all....









Draining the old sucker





Gotta love the right tool for the job.









Car wasn't high enough of course...



OUT!





All without removing the exhaust cross over... WAY easier to deal with not having to take that ou.



Downpipe time...

[3X00-Modified]

Kyle working on his new trans.





After a few hiccups of the parking engagement rod being bad we are ready to go in...



2060 stall converter













IN!


All buttoned up and soaking up the mess we made.



Measuring the downpipe... Yes I need a metal bench to work on... My other bench was COVERED in crap and stuff from Pink car so to the ground I was banished.. LOL



TIG away!





Difference



Next day, After about 2hrs of mind numbing tig welding...





Fill her up!





Installing the downpipe.



Testing the shifting before dropping it and checking for leaks...





Ready for the test ride!

[3X00-Modified]

I hope Kyle's happy with what he ended up with... I know for sure it's better than what he had from what he told me it was doing.

[woody90gtz]

Back in Black rose metallic. haha

[3X00-Modified]

Oh yeah I picked up another core transmission now because Kyle didn't take his home... LOL... that makes 4 cases that I have, 3 of which are complete for the most part... One is Maj's old trans which I stole the park engagement rod from, and it has sat out in the weather for years so is mostly crap, just a good case really.

[Money pit Beretta]

Freaked me out there 3X00, I will never put a car in gear on jackstands. The photos were great and that was a nice way to do it.

[turbotim59]

3X00, Great pics. What paint are you using on the case and does it hold up to the heat? As far as your mods for the drags do you lighten any rotating parts? Getting mine to shift firmer and shorten the time during shifting is a goal for trans work. The 29 / 41 ratio on the th125c is about it's max. The 41 tooth gear is as far as we could go with the case limitations. I don't know just how far I can go with the 4t60 yet. Some measurement will happen first then comes the calculator. The gears are simular in both the th125 and the 4t60 but are dimentionaly different and don't interchange. The 125 has a drive ratio of about 4.5 and slicks are a necessary item for traction. 60 foots at 1.88 and it has a best of 13.76 . Motor is a 3.0 Buick. I hope to get the Beretta into the low 14's as a C/FS NHRA car. It has an index of 15.15 and would have to weight 2883 with me in it. This is why the trans is such an interest to me. I feel that a large portion of my et reduction wil come from the trans verses the motor. Thanks for any info and keep up the work. TurboTim

[Rettax3]

Freaked me out there 3X00, I will never put a car in gear on jackstands. The photos were great and that was a nice way to do it.

I had the same thoughts, although I'm actually nuts enough to do it too. An old co-worker of mine was having problems with his Porsche 944 a couple of years ago, wheel bearings, or CVs, or transaxle hub bearings chattering, he couldn't tell. He flat out refused to lift the car up and drive the wheels in the air for fear of the car coming down (which honestly, it isn't that unsafe or I wouldn't be getting underneath these cars in the first place... ) and taking off. I suggested he take the wheels off and run the car through the gears. Much safer. He traded it in before he ever fixed it...
Nice thread though, Jon.