3 rebuilt 4l60e's later.....

[Supercharged111]

AGREED!
A low mileage 4L85E swap was about $1500 said and done for me. Its not nearly as complicated as some make it out to be. I modified my stock cross member with an abrasive saw, a welder and some plate steel, swapped the yoke to an aftermarket 4L80E slip yoke (on my van it had the same length driveshaft with a 4L60E or 4L80E and even used the same U-joint), replumbed the cooler lines, used a trans connector pigtail I found in the wrecking yard to extend my harness and flashed my PCM with a segment swapped file. I also had to swap the lower portion of my trans dipstick tube, the trans dipstick and the shifter cable. I have given the 4L85E hell and it has never even wimpered and the 4L85E is rated to take its maximum input torque in all gears. With a 2,800 rpm stall purpose built HD towing converter from Performance Torque converters of Texas and a 5.13 gears it vastly outperforms the 4L60E/3.73 gear combination and actually turns less RPM in OD towing than the 4L60E did in 3rd. My empty highway mileage saw a slight decrease but my city mileage actually improved. The custom converter, deep sump aluminum pan, larger trans cooler and shift kit added another $1000 to the swap but I did them later. It runs cool and does what it is supposed to. I change the fluid and filter every 2 years or 24K whichever comes first. I run Dex III, refuse to swap to Dex 6.

GM did not even have the confidence in a 4L60E to put it behind a 4.3 TBI in an 8-lug chassis.

Damn. I was into my 4L80 swap on a 4x4 for just south of $1500 and that was with a rebuild. But you got a good used one and not a core like me.

 

[SUBURBAN5]

Smh.. really depends what kind of driving and abuse you do to the trannys.... no argument 4l80 is a stronger trans but 4l60 did pretty good for us.. but I agree there easy to kill but I'm a rough driver.. treat it nice and there not that bad.. towing , abuse, and heavy truck 4l80e is ideal

 

[SUBURBAN5]

I might be alone on this one but I take a 4l60e anyday before the new garbage there's selling needing multiple service around 40k-80k miles

 

[CRF450R]

I might be alone on this one but I take a 4l60e anyday before the new garbage there's selling needing multiple service around 40k-80k miles

I love my 4l60e I think guys talk **** about them way to much I like them I've had lots of trucks with them and I can't complain. Now I did own a 2008 2500HD with a 6.0 and the 6l90e 6spd with 3:73s and wow loved it unfortunately it was a repo truck I bought for cheap and was kinda trashy but hell 345hp 18-20mpg at 110km/h I loved it and loved that 6l90e I wish there was a way to stuff a 6l90e into my 98. But im thinking lb7duramax plus built 4l80e swap someday so my 98 probably won't get the 6l90e. I love these new transmissions there building now there leaps and bounds better then our 4l60e and 4l80es drive a 2020 duramax with the 10spd Allison with 20k behind you and you'll have a new appreciation for these new transmissions. Although I hate automatic semi's I'll take a 13
Or 18spd Eaton Fuller all day long over a automatic but that's a completely different animal of a truck.

 

[Supercharged111]

You can stick a 6L90 into whatever you want.

 

[CRF450R]

You can stick a 6L90 into whatever you want.

Tell me more!

 

[CRF450R]

Let's say I wanted to find a cheap lb7 motor with harness have it modified to stand alone aswell as a 6l90 to stand alone will my drive shafts need to be modified? How do I retain my original gauge cluster and my original transfer case and pushbutton 4x4 and cruise control? I know the lb7 has a bad rap but there simple cheap and from what I understand gm made them as compact as possible to install into these gmt400s. But the 6l90 is way better then a 4l80 and way cheaper to build up a 6l90 vs a 4l80.

 

[df2x4]

But the 6l90 is way better then a 4l80

Debatable... From what I understand the 4L80E is more durable mechanically, and the 6L90 requires good tuning (and a seperate TCM, even in OEM applications) to make them live. I'm no expert though.

 

[Supercharged111]

Tell me more!

This guy will run a 6L90 with nothing but an RPM and TPS signal. Could put one behind a carb'd motor.

https://www.powertraincontrolsoluti...trol_Modules/TCM2600_Transmission_Controller/

Debatable... From what I understand the 4L80E is more durable mechanically, and the 6L90 requires good tuning (and a seperate TCM, even in OEM applications) to make them live. I'm no expert though.

This is my understanding as well.

 

[stutaeng]

Debatable... From what I understand the 4L80E is more durable mechanically, and the 6L90 requires good tuning (and a seperate TCM, even in OEM applications) to make them live. I'm no expert though.

Um, I thought the 6L80 was a good unit, but my brother's buddy just had his go out at around 102k?! Of course, anything can fail. Maybe that truck was the 1.5%-er?

I know some guys from work have the newer 8L80 and have been to the dealership with complaints about jerky and erratic shifting. All the dealer has done is "reprogram" them, which of course, does nothing. Another buddy has a buddy that got rid of this late model Silverado for the same reason. Seems there's a class action suit on this, based on the internet...Ive ridden with them a few times and have noticed that jerky shifting. It makes
the 4L60 look good, which is a shame...

Certainly not inspiring if you ask me!