Gotta love those 4L60E's(insert sarcasm)

Disclaimer: this is more of a venting/rant post.
Well, last week sure was eventful for me.
Long story short, Wednesday afternoon around 6:30 on my way home a very loud grinding noise decides to present itself. Pulled over, called roadside and after sitting in my truck for nearly two hours I made it home on a flatbed at about 10pm. No reverse with the sound of stripped gears, but moved forward with lots of grinding.

With a rear axle that I knew was not healthy, and a nice amount of frustration on top clouding my judgment I wound up throwing in a surprisingly good looking junkyard axle. About 3/4's of the way through the swap, I come to my senses realize it wasn't the axle. Its the trans, the same trans I spent a nice chunk of money to have rebuilt in Feb of 2018. Luckily for me I got a 3 year warranty on it, unluckily after moving to where I live now the shop is about an hour away and cost me a $300 tow bill to get it out there.

I'm 99.9% sure it's the sunshell, but awaiting word on it when he tears into it at this point.
I've put so much money into this truck its not funny, sad part is I'm not even done fixing it up. Still need to replace my front control arms and such, needs cats, still needs a new cluster, and a handful of small misc. items. Not to mention cosmetic and comfort stuff I want to do to it.
Overall it's a pretty nice truck and is in great shape compared to all the others running around locally, but damn!

I know some guys are swapping out the 60's for 4L80E's and I can see why. Starting to think about keeping my eyes out for a good deal on a 4L80E to have on hand in case I have any more issues with this damn thing. The ridiculous thing is that I don't even tow anything heavier than a golf cart, and I don't beat on this truck.

End rant.

885speed said:

I know some guys are swapping out the 60's for 4L80E's and I can see why. Starting to think about keeping my eyes out for a good deal on a 4L80E to have on hand in case I have any more issues with this damn thing. The ridiculous thing is that I don't even tow anything heavier than a golf cart, and I don't beat on this truck.

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I'm one of those guys, and that was in my V6 truck. Never towed anything heavier than a waverunner. I did beat on mine pretty hard and remove the torque management from the tune though. I killed two 4L60Es and that was enough for me. No regrets swapping to the 4L80E. It was a ton of money and research (I didn't do any of the labor myself), but the truck drives better than it ever did with a 60E. Killed some power off the line but nothing terrible.

I rebuilt my 4l60e a few years ago. It was slow going into reverse. It was in a light duty 95 G30 Van (7600 lb GVW). Yes, not one of Gm's wiser choices. The aftermarket is pretty good at curing most of the l60s weaknesses, if it's built right they can last. I did the rebuild myself using youtube videos. I was an automotive tech for 17 years, but have only done a handful of automatic transmissions. Anyway for towing a combined weight of almost 10,000 lbs (cargo, trailer and van) it did fine after the modifications/rebuild for two years. It was the gear ratio spacing that really sucked for that amount of weight. I did not want to mess with it, or toss the 4l60e on craigslist by itself, so I sold the van for a high price. Its still going, I sold the van to the "hemp" farmers here in Oregon and it still gets loaded down as a delivery vehicle. I now pull the same trailer and chassis dyno with a 4l80e in a c2500, its gear spacing is more useable for towing.

df2x4, so you have a 4L80E behind a 4.3 Vortec? I thought I was reading that wrong? But I (started) reading your thread. Cool!

I thought the 4L60E had longer lives behind the 4.3 due to lower power? Both engine and tranny (4.3/4L60E) on '99 ECSB is starting to go out, but has 250,000 miles, so I'm not complaining. I have a buddy with same setup RCSB with over 350,000 miles and still ticking.

Anyways, back to OP: Man, sorry to hear that. If this is a daily driver I would try to get the transmission warrantied. Maybe something wasn't done right? $300 for towing is still way cheaper than anything else. Making things worse is that you misdiagnosed the rear axle. That's okay. We all make mistakes.

I hope things work out for you.

df2x4 said:

I'm one of those guys, and that was in my V6 truck. Never towed anything heavier than a waverunner. I did beat on mine pretty hard and remove the torque management from the tune though. I killed two 4L60Es and that was enough for me. No regrets swapping to the 4L80E. It was a ton of money and research (I didn't do any of the labor myself), but the truck drives better than it ever did with a 60E. Killed some power off the line but nothing terrible.

Click to expand...

In a previous life I had a 2000 NBS V6 work truck and being younger I gave it hell, and it never blinked an eye.

With the L31 I find myself being pretty easy on the truck, because it's got more than enough power/torque to get up an go if needed without having to punch it.

I rebuilt my 4l60e a few years ago. It was slow going into reverse. It was in a light duty 95 G30 Van (7600 lb GVW). Yes, not one of Gm's wiser choices. The aftermarket is pretty good at curing most of the l60s weaknesses, if it's built right they can last. I did the rebuild myself using youtube videos. I was an automotive tech for 17 years, but have only done a handful of automatic transmissions. Anyway for towing a combined weight of almost 10,000 lbs (cargo, trailer and van) it did fine after the modifications/rebuild for two years. It was the gear ratio spacing that really sucked for that amount of weight. I did not want to mess with it, or toss the 4l60e on craigslist by itself, so I sold the van for a high price. Its stills going, I sold the van to the "hemp" farmers here in Oregon and it still gets loaded down as a delivery vehicle. I now pull the same trailer and chassis dyno with a 4l80e in a c2500, its gear spacing is more useable for towing.

Click to expand...

That's the beauty of "value engineering"

Well, the funny thing is that when it lost 3-4 and was rebuilt in 2018 I asked the guy specifically to use all the beefed up components. I plan on asking for pictures of the failure to see if he put in the better sunshell(if that even is the issue) or just the standard replacement.

As far as getting a 4L80E, It'd be a nice opportunity to rebuild it myself and learn a new thing or two. Only concern would be the drop in fuel mileage some folks say they get after the swap, as currently with the engine running as good as it does I can squeeze out 18.5 MPG by some miracle.

Anyways, back to OP: Man, sorry to hear that. If this is a daily driver I would try to get the transmission warrantied. Maybe something wasn't done right? $300 for towing is still way cheaper than anything else. Making things worse is that you misdiagnosed the rear axle. That's okay. We all make mistakes.

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Yeah, I mean the rear axle needed to be changed anyways. But having a clear mind when something goes wrong is very important. Used to be worse, but as we get older we tend to gain patience with most things.

Thanks, if it does come back as internal failure then it should be covered under the 3 year unlimited mile warranty he gave me. The truck shifted amazing since it was rebuilt, so I'm giving him the benefit of the doubt on his workmanship as of right now.

885speed said:

In a previous life I had a 2000 NBS V6 work truck and being younger I gave it hell, and it never blinked an eye.

With the L31 I find myself being pretty easy on the truck, because it's got more than enough power/torque to get up an go if needed without having to punch it.






That's the beauty of "value engineering"

Well, the funny thing is that when it lost 3-4 and was rebuilt in 2018 I asked the guy specifically to use all the beefed up components. I plan on asking for pictures of the failure to see if he put in the better sunshell(if that even is the issue) or just the standard replacement.

As far as getting a 4L80E, It'd be a nice opportunity to rebuild it myself and learn a new thing or two. Only concern would be the drop in fuel mileage some folks say they get after the swap, as currently with the engine running as good as it does I can squeeze out 18.5 MPG by some miracle.

Click to expand...

I lost 1 mpg city, highway stayed the same in my Express van. On the highway the slightly lower OD gear turned about 200 rpm higher and it held overdrive and lockup better. It would grunt its way up hills that had the 4L60E downshifting a gear on.

stutaeng said:

df2x4, so you have a 4L80E behind a 4.3 Vortec? I thought I was reading that wrong? But I (started) reading your thread. Cool!

I thought the 4L60E had longer lives behind the 4.3 due to lower power? Both engine and tranny (4.3/4L60E) on '99 ECSB is starting to go out, but has 250,000 miles, so I'm not complaining. I have a buddy with same setup RCSB with over 350,000 miles and still ticking.

Anyways, back to OP: Man, sorry to hear that. If this is a daily driver I would try to get the transmission warrantied. Maybe something wasn't done right? $300 for towing is still way cheaper than anything else. Making things worse is that you misdiagnosed the rear axle. That's okay. We all make mistakes.

I hope things work out for you.

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GM put 4L80Es behind 4.3s. The converter works great behind a small block and also works well behind a cammed big block.

I could have pulled and bought 3 different complete 4L80Es yesterday had I had the time. $190 ea with a 13 month warranty.

L31MaxExpress said:

I lost 1 mpg city, highway stayed the same in my Express van. On the highway the slightly lower OD gear turned about 200 rpm higher and it held overdrive and lockup better. It would grunt its way up hills that had the 4L60E downshifting a gear on.

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I would gladly give up 1 MPG for the reliability of a better transmission, lol.

Hills are one thing we don't really have here in Florida though, but if you want to retire, do meth, or have a town mayor give you illegal plastic surgery, then its the place for you! Haha
But that is a whoooleee different topic of discussion!

I could have pulled and bought 3 different complete 4L80Es yesterday had I had the time. $190 ea with a 13 month warranty.

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Can't beat that deal!
Haven't checked locally for one yet, but I'm sure they want a fair bit more than $190 lol.

885speed said:

That's the beauty of "value engineering"

Well, the funny thing is that when it lost 3-4 and was rebuilt in 2018 I asked the guy specifically to use all the beefed up components. I plan on asking for pictures of the failure to see if he put in the better sunshell(if that even is the issue) or just the standard replacement.

As far as getting a 4L80E, It'd be a nice opportunity to rebuild it myself and learn a new thing or two. Only concern would be the drop in fuel mileage some folks say they get after the swap, as currently with the engine running as good as it does I can squeeze out 18.5 MPG by some miracle.

Click to expand...

I had a lot of friends in the same situation. They ask for good parts and get a bigger bill but the same parts. That's why I rebuilt my transmission. I would be the one standing on the side of the road if it went wrong, so I was very careful with part selection and assembly. I used mostly Sonnax parts from their HD build plan. They do cost a bit more but I never was on the side of the road even pulling all that weight.

https://ls1tech.com/forums/automatic-transmission/1875178-1995-4l60e-hd-questions-2.html