opinions on 4L80E converted 6speed automatics

[ULTM8Z]

I've been contemplating a 6-speed automatic for quite some time now. But with the failure of my TH700R4 last week, I've been thrust into the position of having to make a decision now...

Wanted to get opinions on these 4L80E-based 6-speed automatics... (i.e., like TCI 6X).

So far the ones I know about are TCI and PATC. I like having the automatic (as opposed to swapping over to manual 6 speed), but the idea of having the 6 speeds available is very appealing.

I've been reading up online and many of the threads/posts are several years old, and they're a mixed bag of praise and complaints... everything from no problems whatsoever, to having to take the tranny out a few times and sending back to the manufacturer for a refund).

Wanted to see if there have been any more recent experiences with these and whether I should make the attempt.

Thanks.

[rickpaw]

Just to clarify, 4l80e is a 4-spd auto.

Have you looked at the 4l60e version? Supposedly it's the same size as your 700R4 (believe it's the same, other than electronically controlled).

[ULTM8Z]

Originally Posted by rickpaw

Just to clarify, 4l80e is a 4-spd auto.

Have you looked at the 4l60e version? Supposedly it's the same size as your 700R4 (believe it's the same, other than electronically controlled).

Yes, 4L80E is a 4 speed. Sorry, I went back and edited my original post for clarification.

4L60E version? I was unaware of that. Who makes it and what are the opinions on that? My long term future plans may have a 500+ hp 427 sbc, so hp capability is a concern. What I do now needs to keep that in mind.

[Jr]

Rick,

Tci makes a 6 speed auto out of a 4l80E. They are expensive...

For the money, I would use a 4L80E and be done with it.

[ULTM8Z]

Understood it's expensive. I'm really just looking for real world experiences with it. The price is kind of a separate question.

[ULTM8Z]

Interesting development...

Over at Protouring.com, a company called Power trian control solutions came up in discussion.

they make a valve body that converts a 4L80E to a six speed using the overdrive gear as a gear splitter.

Talked to the guys at PTCS just now...

Take it for what it's worth...

I guess they developed the valve body for a military application that, according to the tech guy, was far more brutal on the trans than what I'd subject it to.

Since the car is only driven <5000 miles/year, if the long term durability of the transmission is even partially degraded (which they contend it isn't), seems like it would still last me a long time.

They're stuff to do the conversion is ~$2000 (controller, paddle shifters, valve body, and harness). So if I can get a low mileage used factory GM transmission for ~$1000 or less, could probably do this pretty cheaply. Probably would get the lower gear set too from TCI for $900.

[rickpaw]

Originally Posted by Jr

Rick,

Tci makes a 6 speed auto out of a 4l80E. They are expensive...

For the money, I would use a 4L80E and be done with it.

My mistake. Thought he was just referring to the regular 4l80e, not the 4l80e-based TCI 6x.

Originally Posted by ULTM8Z

Interesting development...

So if I can get a low mileage used factory GM transmission for ~$1000 or less, could probably do this pretty cheaply. Probably would get the lower gear set too from TCI for $900.

If I were you, and dead set on a 6 speed auto, I'd go with GM 6l80e and be done with it. But then I heard the 6l80e is huge and may require cutting the trans tunnel.

[ULTM8Z]

Yeah from everything I've read, the 6L80 doesn't fit.

[rickpaw]

Originally Posted by ULTM8Z

Yeah from everything I've read, the 6L80 doesn't fit.

Well, everything fits with enough cutting.

Been to your site several times, loved what you've done to the car.