4l60e Trans ?'s

ohiogmc · January 19, 2009

Hi everyone....I'm an obvious newb here but was hoping to get some help with my 95 GMC K1500 Sierra 4x4. She has almost 250k on her and the engine is the 5.7L. I've run Royal Purple since I've had her and the engine runs like a top! I picked it up about a year and a half ago and I use it to go to and from the race track.

This past summer I was towing on some back roads and forgot to take it out of OD after getting off the highway. It didn't take long and it starting slipping...then I lost 3rd gear as well. I have 1st, 2nd and reverse. It's the 4L60e and I am finding that it is expensive to fix and difficult to find.

Now the fun part:

1) Can I rebuild this thing myself? I am pretty mechanically inclined and do all my own work on my race car. That said, I do not have a lift and I have the normal set of tools and I am thinking I might have to spend a bunch of money on tools.

2) If yes, is it cost effective to rebuild it? It looks like you can buy some already rebuilt for between $1000 and $1500. Am I going to spend that in parts, special tools and headache?

3) Lastly, I've been told that the 4L60e in the 95 was special for that year. What makes it so special? Are there any other options? ie. can I get a 2WD tranny and swap tail shafts or whatever else is needed?

Sorry for some many questions and thanks for your help!

66nova · January 19, 2009

Hi everyone....I'm an obvious newb here but was hoping to get some help with my 95 GMC K1500 Sierra 4x4. She has almost 250k on her and the engine is the 5.7L. I've run Royal Purple since I've had her and the engine runs like a top! I picked it up about a year and a half ago and I use it to go to and from the race track.

This past summer I was towing on some back roads and forgot to take it out of OD after getting off the highway. It didn't take long and it starting slipping...then I lost 3rd gear as well. I have 1st, 2nd and reverse. It's the 4L60e and I am finding that it is expensive to fix and difficult to find.

Now the fun part:

1) Can I rebuild this thing myself? I am pretty mechanically inclined and do all my own work on my race car. That said, I do not have a lift and I have the normal set of tools and I am thinking I might have to spend a bunch of money on tools.

2) If yes, is it cost effective to rebuild it? It looks like you can buy some already rebuilt for between $1000 and $1500. Am I going to spend that in parts, special tools and headache?

3) Lastly, I've been told that the 4L60e in the 95 was special for that year. What makes it so special? Are there any other options? ie. can I get a 2WD tranny and swap tail shafts or whatever else is needed?

Sorry for some many questions and thanks for your help!

First off, welcome to the site. Lets see some pics of the truck and the race car!

1.) Could you? Probably. Personally, I would not recommend it. At least not with out some guidance. Building a transmission that witll hold up is an art. And there are very few that do it well. Even many that claim to be transmission guys are not great.

2.) I would buy one or have yours rebuilt (I have done both). I like buying one because often it comes with a warranty. I also would not consider buying/building one that they did not install a shift kit in. Any good trans shop will do this. You are there, there is no reason not to increase the line pressure, especially if you are towing with it.

3.) You have been informed correctly. The 95 is a unique transmission. I don't really know why, but there are some differences in the case. But I do think you can use a 2 wheel drive transmission.

Good luck and let us know what you decide to do.

Spurshot · January 19, 2009

This seems like a good time to swap the 4L60e for a 4L80e. What do you think, Bob?

66nova · January 19, 2009

This seems like a good time to swap the 4L60e for a 4L80e. What do you think, Bob?

Wouldn't be a bad idea, but it depends on how much towing/wt we are talking about and I'm not sure it is a bolt in and go situation. That would be something you would have to talk to the trans shop about. The 95 is still an OBD-I system and you cannot just flash it with new programming. Would the computer communicate with it?

A good built 4L60E can handle some towing (sucks that there is now tow/haul mode in 95), just depends on what you're towing.

Also, what gears/tire size does your truck have? A set of gears can definitely relieve some strain on the tranny.

Rat4go · January 20, 2009

Sounds like the 3-4 clutch is toast. Been there, done that (big block in front of 4L60 in a car). Doing a rebuild is a bit of a PITA in that to get some stuff done 'right', you need some special tools. Find a decent shop and tell them that you'll pull and install the trans and see how that 'helps' the cost, and ASK WHAT IT MEANS TO ANY WARRANTY. My wife's uncle used to have a trans shop and pulling the trans and putting it back in was more than half the labor as they always ran into fasteners and cooler lines that were rusted up and ended up replacing lots of that stuff 'cuz the customer didn't want the vehicle to sit for a couple days covered in PB blaster to bust the rust up. It's been a while, but I'd expect that if you did the remove/reinstall, you're probably talking $300-400 in parts (gaskets, clutches, etc) and another $200-300 in labor. This doesn't include shift kit stuff that has been mentioned. If you go the 'shift kit' route, my experience is that you need to be ready for some slam-banging shifts, especially the 1-2 shift. Some shops are a bit hinky about you doing the R&R yourself..with one I dealt with, they said IF there's a problem, I'd get to do the R&R again before they'll work on it. Not the best answer if the issue is something they could have fixed with the trans in the vehicle, but I didn't want a trans shop guy driving my toy anyway, and I could pull the trans in about 45 minutes on my back in the garage, so I was OK with that.

Good luck!

66nova · January 20, 2009

If you go the 'shift kit' route, my experience is that you need to be ready for some slam-banging shifts, especially the 1-2 shift.

This really depends on what kit you go with. Most company's make a stage 1-3 or 4 kit. For a street driven truck, stage 1 is plenty. It will give you nice firm shifts (what you want if you are towing) but not slam into gear.

On my 95 I have a shift kit in it. The transmission shop would not rebuild it with out putting a kit in it. Most would not know that one is there with normal driving, but with heavy acceleration or when towing its nice firm and quick. None of the soft slipping crap.

Now, you would not want the kit that is in my Nova. It will shake the car. It hits hard, but luckily I have enough stall that it smooths it out for street driving.

ohiogmc · January 27, 2009

Thanks for the info guys...it is much appreciated. After carfeful consideration I purchased a rebuilt unit and torque converter for just under $600. It comes with a shift kit and redline clutch packs installed and a 1 year warranty. They'll arrange a call tag for my old tranny once the new one is installed. It should be here next week.

Does anyone have any service instructions on the removal and install for this??

To answer the questions that were asked in the thread:

-towing: I tow a 20' enclosed trailer (~2950 lbs) with a BMW track car (~2850 lbs) --see pic below

-stock wheels and tires

-stock gear (as far as I know)

custommiller · January 27, 2009

ohiogmc, where did you find one for under 600.00. I have a 1994 gmc Z71 w/255000 on it and im going to do engine and trans overhaul soon.

J-man67 · January 27, 2009

Yeah, thats a great price. Nice trailer and car too man!

66nova · January 27, 2009

Good looking rides!

That's a heck of a deal on a 4L60. Especially condidering it has a 1 year warranty.

ohiogmc · February 19, 2009

Thought I'd give you guys an update. The trans finally arrived but the torque convertor got lost in transit. They are sending a replacement and upgrading to a 3 year warranty for the trans.

Does anyone have disassembly/reassembly instructions on a trans swap?

Thanks,

J

edit: custommiller: I bought it from Transmission Parts Distribution in Saginaw, MI 1-800-474-2415 ask for Jeff.

Rat4go · February 19, 2009

I don't have a lot of specific details on the R&R, but I do know that you need to be REALLY careful when you set the converter into the trans. DO NOT put the trans on a stand and tilt it so the front of the trans is up to make installing the converter easier...you're more likely to have gravity help you drop the converter on the pump and this is BAD. The converter hub has notches in it that engage the pump. If you don't have things lined up, or even if you do and you just drop(or force) the converter hub into the trans, you run the risk of hurting the pump rotor because that's what the converter bottoms out on. It may not be obvious right away, but one of my buddies had a rotor blow up 2 days after he installed the converter/trans. Looking at the broken parts, it looks like there was a mark from the converter hitting the tabs on the rotor that likely caused the damage. He put the converter on the trans while the trans was on a stand and just 'dropped' it on. New pumps aren't super expensive, but doing a pump swap means pulling the trans again.

Again, I've never done a tranny swap on a torsion-bar-equipped truck. My guess is that your biggest issues will be with getting the exhaust and the torsion bar x-member out of the way. Any trans swaps I've done were sorta straight-forward....start by removing everything on the trans or in the way of pulling the trans, then reverse the process when you're done.

Good luck!