Koshka73

I have a problem that I have not been able to solve with the posts that I have been able to find here. I am trying to install a 4L60e onto a LQ4 that originally had a 4L80e. I removed the original flexplate with the spacer and replaced it with a (1) dished, (2) flat and a (3) TCI model that was "guaranteed" to fit... No luck. The problem that I am having is that all the flexplates sit so far away from the engine block that the TC pushes against it when the transmission is bolted on and causes the engine to lock up. So I've measured the distance from the block face to the boltholes on the flexplate (6/16") and compared it to the front edge of the transmission to the bolt flanges on the TC (14/16") and found that there is about a half inch overlap.
Is this a flexplate issue, a problem with the TC, or something I haven't identified yet?
I am running out of ideas and I don't have the money to keep buying flexplates and hoping that they'll work. And yes, I have made sure that the TC was FULLY seated on the tranny before attempting to put them together. The TC actually rubs a bit on the inside of the transmission bell housing when pushed all the way down and rotated. I figured that it would be pulled away enough for clearance when mated to the flexplate.
Please help, I've asked local shops and online stores for help and no one seems to know!

LS1MCSS

iTrader: (18)

Did you remove the spacer that was behind the original flexplate? The curved flexplate should work fine. Post a picture of the end of the crank so we can see it.

mcdonald77

iTrader: (21)

I was thinking the same thing. Theres a threaded hole you can insert a bolt in to and pull off the spacer.

Koshka73

I did remove the spacer, it came off with the original flexplate. I have included a few pictures.
1. Picture of the flexplate installed with the spacer shown in the bottom right hand corner.
2. Top down picture of the flexplate.
3. Profile picture of the 4L60E where you can just see the end of the TC.
4. Torque Converter installed.
5. The transmission installed on the engine at the point where the TC contacts the flexplate.

99VetteFRC

From what I see you should use the the dished flexplate as you are using the stock 4l60e convertor. I think the flexplate you have would be used on a 4l80e since it has 6 holes. It also looks like the flexplate has spacers on the bolt holes so the crank spacer wouldn't be used. That is just my observation from your pics.

Koshka73

That was one of the first ones that I installed however, I had the same issue with the transmission not fitting up to the engine without the TC contacting the the flexplate.

The six holes are for either a 4L60 or 4L80.

99VetteFRC

Not sure, but that is a stock style conreter right? If it is it should just bolt right up to a stock 5.3 flexplate with no spacers. What is the trans out of?

99VetteFRC

Is it possible you have an early trans and a later converter? It looks to me like the coverter isn't going in the trans far enough. However I don't have a late 4l60e to compare it with. I don't thein the snout should be sticking out past the bellhousing surface. I know you said it was all the way in but maybe its not on the pump ears all the way. Could the trans be off of a 4.3 and use a different converter?

thump16

look at your converter being too big. I have an 04 LQ4 with a 97 4L60E trans and I used the stock 6.0 flexplate that came with the spacer to attach the 97 yr model torque converter. I also elongated three of the mount holes to match converter pattern. Originaly, I had a 05 4l65e converter and it was too big. Hope this helps.

Koshka73

Not sure what it is out of. I purchased it from a local company that also supplied the torque converter based on the engine I told them I was putting it in.

That may be the issue. Perhaps I can find a used one to try out before buying more useless parts!! Thanks, I'll let you know what happens.

ls68firebird

i had this same problem. The torque converter they gave me was wrong, and it would feel like it was all the way down but it wasn't and never could be. the center shaft (the one in the very middle and sticks out further) of the trans was too big for the converter inside. so it bottomed out on that and didn't go down. Called the trans shop and they gave me the right one, and bingo - everything lined up.

Koshka73

Okay, after way too much time spent on this one issue I took the morning and called every shop in town that had to do with performance or transmissions or auto parts or anything remotely likely to help. I finally found a shop (Transmission Clinic) that asked me to bring them the transmission and they would figure it out.
SOOOO, Long story - short...
The transmission that I purchased had a bellhousing that was made for the LS1/car engines and was shorter than what I needed for the truck TC (which seems to be larger).
Anyway, $25 later and a Nused bellhousing and I was off. Did a test fit tonight and everything's looking good.
Thanks to everyone for the help and pointing me in the right direction. I'd still be floundering with you.

99VetteFRC

Glad you got that figured out. Good luck.

1duffman

Ok so I was look up something else for my LQ4 and ran across this. So i figure I will ask my questions now. I am in the middle of the same issue, but i have a 2000 LQ4 trying to mate to a 96 trans. I didn't realize before I bought the motorthat the crank in the pre 01 6.0 is a tad longer. Now I'm not sure how much this will affect attacting the two and I havn't quite gotten to the point of mock up( I'm in school and someone else is using the hoist, so I'm stuck on the stand for now). But so far I've gotten to the point of getting a 5.3 flexplate and a template to elongate the bolt holes in it. This flexplate is pretty dished though and i'm wondering if it's gonna screw me, one way the dish hits the converter and the bolt hit the cover bolts, and the other way the conv. just seams to be so far away from the end of the crank that the bellhousing wont contact the block.
I don't know if you answerd this in the thread but I just wanna make sure of everything. Can someone let me know if that will work out? Or if I will have to do more. Thank you guys

LS1MCSS

iTrader: (18)

I don't think you can use the dished flexplate at all. You're probably going to have problems with the 96 model tranny too. Pull the convertor and see if the tranny is marked PWM. If not, it won't work at all.

Old Geezer

iTrader: (3)

AIRC, I had 2 bell hsgs for a mock up trans. They were right at 9/16" difference in length..

TexFGuy2526

Hey guys, I dont mean to steal/interrupt the thread here, but Im doing a similar swap on my daily driver and need some help...I have a 2004 silverado 4.8L/4L60E That I am swapping a 2003 LQ4 into...so far everything has gone according to plan. I have only one issue at this point. My trans has the round plug for the top and a single large rectangle plug on the driver side by the PRND lever and the harness that came with the lq4 has the round plug for the top but it has two smaller rectangle plugs in place of where my single large on is...any Ideas on how to make this harness work? Thanks in advance

SS409

Does your tranny have a connector like this one?:



and your engine harness has connectors like this?:





If so, you could spice your 2004 connector on to the 2003 harness, or purchase a pnp switch with the older 2003 connectors.

TexFGuy2526

Yes, that is the connector that my tranny has

TexFGuy2526

Thank you very much...I was kind of at a loss. I have one more question though. The motor Im putting in the truck came with the pcm. Do I need to have it reprogrammed to run the 4l60e or can I just plug and play?