ChiefsPlanet - View Single Post - Home and Auto ***Official Car and Gearhead Thread***

**hometeam** · 08-30-2018, 03:20 PM

I would like to tell the saga of my 4l60e transmission.

So im not sure if I mentioned it here, but after I built the motor in the truck, got everything dialed in, and about 3k miles on it, the 3rd/4th band in my 4l60e let go.

Because I already had a good converter, I told myself I would skip the 4l80 and do just a built 4l60e since I'm putting out less than 500 crank horse in the truck and plan to stay that way. That way, little bit cheaper trans, easy install and go, and keep my same converter.

So I have a local known guy that only does 60s build me a trans. 1100 bucks. heavy heavy built 4l60E. And now if you know anything about 4l60s, a heavy built trans can only handle about 500hp, but I digress.

Me and my buddy install it ourselves in his shop, trans shifts great. But there is a problem. The converter wont lock up. We try tons of stuff, changing tune, commanding it to lock with the laptop everything. And it wont. This points to a converter issue. But, because the trans is warrantied, I take it to my trans builder just in case. Turns out, converter is trashed. When the 3/4 clutches burnt out, they sent so much trash into the converter that the lockup clutches cant engage.

Ok, so the truck sits for a week, I order a new converter from Revmax, (awesome company btw) and my trans builder puts it back together. I pick it up, drive it home, drive it to work and back the next day. On the way back, I notice it gets to 190 degrees trans temp on the highway.. now, this might be normal for a normal setup, but I have a big Hayden bar and fin cooler that should keep the trans about 40-50 degrees cooler than that. I chalk it up to brand new clutches and drive it to work again the next day. Problem is.. I only make it about ten miles before I lose EVERY gear. Trans is completely wasted after only about 120 miles driven.

Once again, I've got warranty, so I have the trans guy come pick it up and pull it to his shop. He opens it up and tells me its the most roasted clutches hes ever seen, and it wasn't his build that did this. I'm pretty easy going so I say ok well lets find out wtf happened.

He rebuilds the trans with all new clutches, new pump, new valve body, everything trying to figure out what happened. Everything is new and golden, and he reinstall trans. THIS TIME, he puts a pressure gauge on just to see whats going on and immediately sees an issue.

This is the part that you guys will like. This thing has no pressure off the gas. There is NOTHING in the trans that should allow it to run 10psi idle and 15 in reverse. It should be 75/120 respectively. Under load, pressure is fine, but off load it has no fluid pressure. Now, a 4l60e keeps a band engaged when its not under load, so this is what caused the built trans failure, (and likely the very first one) since it had no pressure, the clutches burnt up trying to engage constantly. With the scan tool hooked up, the voltage to the pressure solenoid is solid on the gas, and going crazy off the gas, which is why the solenoid isn't commanding pressure when its off. So, we switch out the solenoid, same thing. We mess with the tune, same thing. Really starting to piss me off, and hes stumped, since we can command the pressure solenoid with the scan tool to hold pressure and it will. I start thinking about it, and I told him that I noticed on startup sometimes, the trucks dash lights would waver and dim just a tiny amount, and I wondered if that had anything to do with the voltage fluctuation. So, I tell the trans builder that I have an extra alternator at home, and lets just try that before I go to a vacuum modulated pressure setup and get rid of the electronics entirely (another 200+ bucks)

We stick the alternator on and INSTANTLY have pressure at idle, 75/120 just like it should be. That ****ing alternator wasn't supplying the right voltage to the EPS and burnt up the god damn trans in 120 miles! I have never seen anything like it in my life!

So, now here I am, paid the man for the extra parts and labor that my truck burnt up with its shenanigans, so deep into this 4l60e I could have had an 80. Lesson learned I guess!

TLDR; Moral of the story, 4l60Es are pieces of shit and check your charging system folks!

08-30-2018, 03:20 PM	#4407
hometeam Supporter hometeam's Avatar Join Date: Jul 2011	I would like to tell the saga of my 4l60e transmission. So im not sure if I mentioned it here, but after I built the motor in the truck, got everything dialed in, and about 3k miles on it, the 3rd/4th band in my 4l60e let go. Because I already had a good converter, I told myself I would skip the 4l80 and do just a built 4l60e since I'm putting out less than 500 crank horse in the truck and plan to stay that way. That way, little bit cheaper trans, easy install and go, and keep my same converter. So I have a local known guy that only does 60s build me a trans. 1100 bucks. heavy heavy built 4l60E. And now if you know anything about 4l60s, a heavy built trans can only handle about 500hp, but I digress. Me and my buddy install it ourselves in his shop, trans shifts great. But there is a problem. The converter wont lock up. We try tons of stuff, changing tune, commanding it to lock with the laptop everything. And it wont. This points to a converter issue. But, because the trans is warrantied, I take it to my trans builder just in case. Turns out, converter is trashed. When the 3/4 clutches burnt out, they sent so much trash into the converter that the lockup clutches cant engage. Ok, so the truck sits for a week, I order a new converter from Revmax, (awesome company btw) and my trans builder puts it back together. I pick it up, drive it home, drive it to work and back the next day. On the way back, I notice it gets to 190 degrees trans temp on the highway.. now, this might be normal for a normal setup, but I have a big Hayden bar and fin cooler that should keep the trans about 40-50 degrees cooler than that. I chalk it up to brand new clutches and drive it to work again the next day. Problem is.. I only make it about ten miles before I lose EVERY gear. Trans is completely wasted after only about 120 miles driven. Once again, I've got warranty, so I have the trans guy come pick it up and pull it to his shop. He opens it up and tells me its the most roasted clutches hes ever seen, and it wasn't his build that did this. I'm pretty easy going so I say ok well lets find out wtf happened. He rebuilds the trans with all new clutches, new pump, new valve body, everything trying to figure out what happened. Everything is new and golden, and he reinstall trans. THIS TIME, he puts a pressure gauge on just to see whats going on and immediately sees an issue. This is the part that you guys will like. This thing has no pressure off the gas. There is NOTHING in the trans that should allow it to run 10psi idle and 15 in reverse. It should be 75/120 respectively. Under load, pressure is fine, but off load it has no fluid pressure. Now, a 4l60e keeps a band engaged when its not under load, so this is what caused the built trans failure, (and likely the very first one) since it had no pressure, the clutches burnt up trying to engage constantly. With the scan tool hooked up, the voltage to the pressure solenoid is solid on the gas, and going crazy off the gas, which is why the solenoid isn't commanding pressure when its off. So, we switch out the solenoid, same thing. We mess with the tune, same thing. Really starting to piss me off, and hes stumped, since we can command the pressure solenoid with the scan tool to hold pressure and it will. I start thinking about it, and I told him that I noticed on startup sometimes, the trucks dash lights would waver and dim just a tiny amount, and I wondered if that had anything to do with the voltage fluctuation. So, I tell the trans builder that I have an extra alternator at home, and lets just try that before I go to a vacuum modulated pressure setup and get rid of the electronics entirely (another 200+ bucks) We stick the alternator on and INSTANTLY have pressure at idle, 75/120 just like it should be. That ****ing alternator wasn't supplying the right voltage to the EPS and burnt up the god damn trans in 120 miles! I have never seen anything like it in my life! So, now here I am, paid the man for the extra parts and labor that my truck burnt up with its shenanigans, so deep into this 4l60e I could have had an 80. Lesson learned I guess! TLDR; Moral of the story, 4l60Es are pieces of shit and check your charging system folks!
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