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4L80E Questions

9134 Views 16 Replies 6 Participants Last post by  Machman
I've decided that I'm going to be bolting an automatic to the back of my 4BT. I can drive stick, and you can call me a pansy all you want, but I REALLY don't wanna sing "row, row, row your truck" every day during my commute on surface streets through downtown Knoxville.

And, while the intended recipient of this repower currently has a 700R4 that has delivered sterling service, I'm thinking that for the long run a 4L80E might be better. If I can get more power via turning a few screws, it's likely those screws will get turned. 4L80E seems to be the answer if you're adding more power.

Don't get me wrong.. The 700R4 I have now is at 220K and shows no signs of giving up anytime soon. When my Dad had it, it spent a significant amount of time with a 30' camper dragging behind throughout the US, Canada, and Mexico. In overdrive... When it wasn't doing that, it was just as likely to be at Lowe's getting WAAAAAAY too much ready-mix or lumber loaded on it. When I got the truck, the transmission fluid was a rich brown color, with a burnt nutty aroma. I asked Dad if he'd maybe gone a bit over the recommended interval for fluid change.. "It's not been changed since it boiled over on that hill at around 25K miles.." As I look down at the odometer showing 130K at that point..

Anyway, in the process of researching the 4L80E option, I've run into one $nag: The controller.

Yes, I'm fully aware of the Compushift offering, but my wallet has to breathe slowly in a paper bag every time I look at the price tag on one of those. Other companies' offerings are similarly priced. Also, I'm not interested in the full-manual conversion on the 4L80E for this vehicle.

So, in the quest for doing things a bit cheaper, and from the angle of repair parts availability in the event of a breakdown, I'm wondering about the stand-alone controller that was used on the diesel (and some gassers, possibly??) 4L80E equipped trucks in the 92-93 or 94 years.

The controller itself seems to be readily available:

GM Part number: 16147609

Standard Auto # TCM609


Pricing for that is more in line with me eating something other than Ramen for an extended period (not that I'd REALLY be harmed with a bit o' weight loss - might get me another .2 MPG or some such, too..). In fact, the pricing I've seen would allow me to carry a spare! But, there are some questions I've not been able to answer through Google and looking here:

1. Has someone actually used the factory controller for the 4L80E behind a 4B/6B w/ VE pump? And, how do you like it?

2. What is needed, besides the controller? Obviously, we're talking a wiring harness of some sort, and from what I've read so far, there's going to be a TPS needed. I also suspect a tach signal would be desired. Anything else? Schematics / wiring diagrams / pictures / part numbers / sources would be GREAT.

3. Programming / tuning needed?? I have no issues with doing a PROM burn, but wanna know up front if I'm going to need to set up for that..

4. What are the differences, if any, between a 4L80E for gas and one that is for diesel? I know we're probably talking torque converter stall speed, but anything significant?

Anyway, any info is appreciated..
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id be curious what a prom burn is going to cost? plus how much is the gm controller going for?

i think the gas and diesel 4l80e is the same, just different computer and tq converter
thats why i just bought a compushift. i can dial all of it in on the "fly". and "see" what is happening.

time is money to me. and ive spent WAY to much of both on my swap
im in gulf shores on vacation till this weekend. i HOPE to have it running within a week of getting home...... we will see.
maiden voyage SHOULD be tomorrow. got my tach up and working.
been busy.

i picked up a tack sending unit from compushift. i took a piece of 3" pipe, cut it and grooved it and made a plate to bolt to the pulley. i came off the front motor mount support and mounted it near the pulley. it WORKS!

of course, i put in a 16,000lb 2 post lift w/ weight gauge and my truck is 6300lbs w/o seats, glass or finished.....
1 - 5 of 17 Posts
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