2007 Suburban, 5.3L - 4L60-E, engine locked up

rhunley · January 19, 2020

I have a 2007 Chevy Suburban 5.3L, 4L60-E tranny with 170,000 miles. The tranny was completely rebuilt about 8,000 ago. One morning I started it with the remote. It ran for a few minutes and then made a weird noise and died. The noise was something like a gurgle but it was quick and then it died. I raised the hood and tried to re-start it. It turned over and ran for a few seconds and then died. After that it would only click when I tried to start it. I took the belt off and everything spins just fine. I put a pull handle on the crank and it would not budge either way. Then I got under it with a large screw driver and the fly wheel wouldn't budge either. I pulled the engine with the torque converter still attached. When I tried the unbolt the torque converter the engine spun. At that point I could spin the engine easily with the crank bolt.....I put the converter back on the tranny and it spins freely and with no friction or noise...I went through the engine and everything was near perfect. I couldn't find anything wrong.... I re-installed the engine. Attached the tranny bolts finger tight. Put the 3 converter bolts in with no problem...The engine turns over easily with the crank bolt...But when I tightened the tranny bolts the engine is just like before. Seemingly locked up... I guess my next move is to pull the tranny. Has anyone ever ran across this problem? Frustrated in Tennessee..

rhunley · January 20, 2020

What year of 4L60e transmissions will work in my 2007 Chevy Suburban?

Thanks

davester · January 20, 2020

So the engine will crank over and run if you unbolt the torque converter from the flexplate?

And I believe you want a 2007 4l60e if you are replacing the transmission. The transmission may have a sticker on it that lists what year it is, and if it does, you'll want one from that same year.

rhunley · January 21, 2020

D, The engine locked up while idling. It wouldn't budge until I unhooked it from the tranny. Now I've built the engine and installed it.

I hooked up the torque converter to the flexplate while the tran bolts were just finger tight. There was about an 1/8 or so gap between the block and the tran. The flexplate and the converter spun easily while I hooked up the 3 converter bolts. But when I tighten the tran bolts it locked up again. When I loosen them it spins freely again. I know that something is in a bind but can't figure out where. And, what caused the lock up in the first place. Thanks for confirming the 4L60e question. I'm looking ahead to possibly changing the tran. The day before this happened I pulled my camper about 130 miles with no issues. Engine oil pressure was good and the engine temp. and tran temp. were good. (tran never got over 180) Thanks for your reply.

rhunley · January 24, 2020

Still looking for some help. Has anybody ever heard of this happening.

swathdiver · January 24, 2020

Pretty certain that you need a new torque converter and you ought to inspect your flex plate real good. That transmission was used in the SUVs behind the 5.3 in 2007 and 2008. The 4.8s also used it, until around 2010 I think. The pickups of the same body style, GMT-900, also used the same setup but for a little longer. Using an older transmission will have different plugs if memory serves.

Start with the converter though.

rhunley · January 26, 2020

James, I'm 61 years old, and have spent most of it building chevy's. But, I've been out of it for a while. I've never seen a torque converter lock up an engine. Is there something about these newer ones? The converter will still spin freely on the trans. and the engine spins freely before I tighten up the tran. I know it sounds weird. Would the converter have locked up the engine while it was idling?...Also, the flex plate looks nice a straight and all the teeth look good. Thanks for your input.

swathdiver · January 27, 2020

9 hours ago, rhunley said:

James, I'm 61 years old, and have spent most of it building chevy's. But, I've been out of it for a while. I've never seen a torque converter lock up an engine. Is there something about these newer ones? The converter will still spin freely on the trans. and the engine spins freely before I tighten up the tran. I know it sounds weird. Would the converter have locked up the engine while it was idling?...Also, the flex plate looks nice a straight and all the teeth look good. Thanks for your input.

Ricky, I can't say for sure over here but I do know that the clutch inside a torque converter can lock up. When it does it will stall an engine and prevent it from starting again. Don't know much more than that on this topic though. I do remember my first transmission build, my mentor said to make sure I installed the converter right by hearing so many clicks, can't remember anymore. I thought I did but didn't and the motor would not turn over until I took it back out and did it right. I think your problem predates such as you were having the problem beforehand.

StevesSilverado · January 27, 2020

A way to check if its transmission related is put the truck in neutral and see if it starts/ runs. If it does run but stalls when you put it in drive, it's most likely torque converter related.

rhunley · January 28, 2020

James, Steve, thank you for your comments. It was just idling in park when it originally died. I'm an engine guy not a trans guy. But, When ever I've installed a converter, I always turn it back a forth until it seats and actually scrapes the bell housing. Of course when you bolt it up it pulls forward enough to provide the gap. I'm fairly familiar with workings of the auto trans. But, is there anything inside that could have broken that would put the converter in a bind? The strange thing is. I can turn the engine and converter with the crank bolt easily up until about 1/16th gap in the trans and engine block. Once I torque it down everything locks up! Anyway, thanks for your input.

davester · January 28, 2020

Can you still spin the TC when it's up against the flexplate, but not bolted to it? And does the TC touch all 3 mounting points on the flexplate when it's pulled out and aligned with the flexplate but not bolted to it?

And since it sounds like the transmission can be moved back from the engine (or the engine can be moved forward), I would suggest separating it a bit, then seeing how the torque converter rotates as it is moved further and further out of the transmission.

rhunley · January 29, 2020

D, Thanks for the advice. I'll go back a try the suggestions. When I originally bolted up the TC the tran wasn't torqued up and it spun around by turning the crank bolt in order to put the 3 bolts in. I've taken the tranny loose several times since to check clearances. I'm always careful when installing the TC. It was seated deep enough that it scrapped the back of the bell housing.

With everything torqued up you can't budge the flexplate or turn the crank bolt. But, I loosened the tranny and put 1/16th shims at each bolt hole and then torqued it down. Now you can turn the engine with the crank bolt! I know it must be in a bind. But, this is exactly what it did when it locked up while idling. Could something have broken or shifted in the tranny? I don't think so but I'm not a tranny man. Thanks

davester · January 29, 2020

I would keep the TC unbolted, bolt up the transmission to the engine, then see how the TC spins and if it's offset/angled at all from the flexplate.

Then, if it looks good, put in one bolt between the TC and flexplate, and see how the engine spins, then one more, spin it again, and then the final one.

Offhand, the only thing I can think of that would do something like this is if the alignment pins between the engine and transmission aren't there or bent/shifted, so they aren't properly aligned anymore.

StevesSilverado · January 29, 2020

When you put the new transmission in did you put a rebuilt converter in? I was a trans mechanic for 10 years and we would see rebuilt converters that were cut to thin. When pulling them forward to the flywheel they would barely be still in the trans pump. Eventually they would strip the pump out and lock the trans up with metal shavings.

rhunley · January 30, 2020

Steve, The trans was rebuilt by the previous owner but the bill says they put a new converter on it.....Before I put the motor back in, I sat there and spun the converter multiple times and it was very smooth. When it was fully seated it slightly scraped the bell housing. This weekend I'll get out there and use the advice from "D" above just to satisfy my brain.. But, what I keep coming back to is what happened in the first place? I really appreciate everyone pitching in their advice and knowledge.