Opinions on 4L80E converted 6-speed 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 the 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.

[Barrrf]

Sub'd - also wanting to see some feedback on these

[BonzoHansen]

I thought at one point Jake was working on something along these lines. Not sure if he got that far or if i remember wrong.

Also i remember pcs offered this. https://www.powertraincontrolsolutions.com/Vehicle_Manufacturers/Products/6-Speed_Automatic/6-Speed_4L80/

[ULTM8Z]

Yeah I've been talking to Jake. He's not to keen on these things and I believe he abandoned his attempt at making one.

[ULTM8Z]

Also i remember pcs offered this. https://www.powertraincontrolsolutions.com/Vehicle_Manufacturers/Products/6-Speed_Automatic/6-Speed_4L80/

Interesting... just a valve body change and you have a 6 speed 4L80E.

The only thing is the factory 4L80's have 2.48 first gear. TCI and PATC put a 2.97 first gear in theirs from what I understand.

[csouth]

PCS also offers a valve body conversion if you already have the 4L80E vs buying new one.

https://www.powertraincontrolsolutions.com/Performance_Aftermarket/Products/Transmission_Products/6_Speed_Valve_Body/

[ULTM8Z]

Talked to the guys at power train control solutions...

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.

[DreKoushRanada]

Talked to the guys at power train control solutions...

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.

This seems like a good idea you have going on there. I was going to get a 6 speed manual but abandoned that idea. This 6 speed automatic seems pretty cool.

[srh3trinity]

I looked at this some time ago. Pretty pricey. The 6l80e and 6l90e are more widely available and can hold a lot of power. They do cause some packaging issues and I don't know how many people have figured out the control setups.

[ULTM8Z]

Yeah the problem is I can't fit it into the transmission tunnel. I also think it has the same wide 1-2 hear spread problem.

[ryanleiker]

I'm in to hear more thoughts on this...

[professor_speed]

The main problem is that to get the two extra "gears" it uses the OD section to essential split the 1st and 2nd gears. without a gear set change 5 gears are more practical. if you set it up as a 6 speed you have used the OD section 3 times, it simply wasn't designed, and really can't be built to come on and off that many times in such a short period reliably. I believe PTCS stopped making this set up. TCI still sells complete 6 speed transmissions. The other problem is that to make it work you won't have engine braking. You are better off with a 6l80/90 if you need 6 gears.

2.48, 1.48, 1.00, 0.75, R2.07 Stock 4 sp

2.48, 1.86 (1st od), 1.48, 1.00, 0.75, R2.07 Stock gear ratios 6sp with valve body (using 5 gears)

2.48, 1.86 (1st od), 1.48, 1.11, (2nd od) 1.00, 0.75, R2.07 Stock gear ratios 6sp with valve body

2.98, 1.57, 1.00, 0.75, R2.46 Low gears 4sp stock 4L80E valve body

2.98, 2.24, 1.57, 1.00, 0.75, R2.46 low Gear Set 5 sp with valve body set up

2.98, 2.24, 1.57, 1.18, 1.00, 0.75, R 2.46 low gear set 6sp with valve body set up

[andrewb70]

Given enough power 4 gears is more than enough! LOL

Andrew

[Craig@Bowler]

The main problem is that to get the two extra "gears" it uses the OD section to essential split the 1st and 2nd gears. without a gear set change 5 gears are more practical. if you set it up as a 6 speed you have used the OD section 3 times, it simply wasn't designed, and really can't be built to come on and off that many times in such a short period reliably. I believe PTCS stopped making this set up. TCI still sells complete 6 speed transmissions. The other problem is that to make it work you won't have engine braking. You are better off with a 6l80/90 if you need 6 gears.

This is exactly the reason why you see so many mixed reviews. PCS discontinued their valve body kit to do this so TCI is the only one left still building them. We built a few a couple years back with the PCS valve body and we found that if you can get the tune down correctly they will hold up decently, but each one has to be tuned to the car/truck that it is used in. With the reliance on the OD clutch pack for the gear splits they are very sensitive to applying the proper amount of pressure to keep from burning up the OD clutches. Those settings are different for every vehicle weight/engine/gear/tire size combo.

[peterwollman]

Guys,

After researching for months and finally installing a brand new 6x in my 1971 Camaro, which has complete frame off restoration and is pro-tour car with a 450 HP LS motor with a 3.42:1 posi-traction rear-end. I had readall the literature and the TCI installation/operation instructions, etc. before buying their expensive transmission package. Uponmy first test drive with the transmission, I noticed it was not "engine braking". I immediately called tech support and found that my original tech was out, however another tech answered and said oh those transmissionsdon't engine brake, WHAT the first tech never mentioned this fact? I wasabsolutely shocked and in utter disbelief that my brand-new state of the arttransmission had no engine braking. TCI’s states in their advertising for this transmission is that it is the "most functional and modern drivetrain combination on the market", which is continually represented in the literature. Nowhere in any of their literature or installation instructions does it mention the "fact" that “engine braking” is not available in this transmission. I have written a registered letter to the company and been contact by one warrantee person and basically they have no plans to build an engine braking valve body. They say most people don't care about engine braking; I said then don't advertise this transmission for Pro Tour cars.

If feel like a complete fool, do you have any advise for me. I saw that the PCS valve bodies include engine braking, so I cannot understand TCI's position on this, but it is false advertising for sure and I feel used.

Thanks
Pete

[ULTM8Z]

Oh man... I can sympathize.

I got burned on a 6 speed 4L80 a few years ago as well. I won't mention the name of the company I bought from given the agreement we reached. It wasn't TCI though.

This one had the PCS valve body and the TCI gear set. It ran well, the problem was the gear whine in first and second gear was horrendous. Sounded like a UPS truck with a worn out transmission. I tried different fluids and other adjustments with advice from the seller, but to no avail. Almost sent it to TCI to have them inspect the gears since the gears were theirs. They said they would look at it and cover the cost if they determined it was an issue with their gears. But after weighing the risks, I decided it wasn't worth the hassle and by that time I too was too pissed by the situation. Worked out a return with the seller for a restocking fee.

Ended up just doing a Gear Vendors (which ironically was my original plan before I learned about the 6-speed 4L80e). Ended up being less than half the cost and I now have 8 speeds instead of 6. Yeah, I don't have the paddle shifters and the computer controlled bells and whistles, but I'm having a blast with it anyway.

All I can say is try to work out a return with them and hope they take what you're saying to heart...

[peterwollman]

Yes I remember you from the Nastyz28 site, we discussed the 6x before I bought it, but I should have asked you about "engine braking". The noise is not bad in my car, but I am so upset as I believed that I would be able to use sport mode with my Lokar Shifter and be able to drive like it had a manual trans or any modern automatic trans! I have countless hours of work in this conversion and not to mention the cost! My letter to TCI was very specific about how they are misrepresenting this transmission. A new valve body is not in works and in fact the guy that designed the transmission passed away, and no one there can tell me any technical information, and there techs useless. I haven't asked for a refund yet but I certainly told them I would put the word out on the internet about their most modern drivetrain combination on the market. At first they tried to tell me no one is complaining, but I know now that I am not the only one who has complained to them about the lack of engine braking.

I talked to PCS today and they don't make their vbm-2000 4l80e 6-speed valve body anymore which had engine braking, and they could not tell me if it would work with the 6x and TCI TCU.

[ULTM8Z]

In all honesty I'm enjoying the gear vendors more than I would have the 6 speed. The 2 extra speeds makes a big difference.

Plus I can just run my 700R4 normally if I don't want to engage the GV for just average around town driving.

[peterwollman]

I have pushed TCI as hard as I can on the Engine Braking issue and the won't even let me talk to an engineer about the transmission, and it does not appear that they will even consider making an updated valve body. I am really upset, and they now say I can return the 6X for a refund. I have so much work into this 4L80e 6X project in my 71 Camaro, and so now what, tear it all out. PCS used to make a engine braking 6speed value body (PCS VBM-2000), but even if I could find one as the are discontinued, would the TCI/Fast TCU be able to drive the solenoids in the PCS valve body????? Wouldn't you think someone would make a valve body with engine braking for this application or at least be able to mod TCI's value body. Does any know an expert that I can talk to? I keep hearing about a gentleman named Jake, would he know?

[ULTM8Z]

Jake's transmissions.

http://www.jakesperformance.com/

Extremely knowledgable guy.

I went through the same thing as you... configured the car for a 4L80E... cross member, transmission lines, wiring and TCU, etc... spent so much time trying to set everything up so nicely and then had to rip it all out. What a @!#%-ing boondoggle that was. Very painful...

[Vimes]

It's a shame TCI stopped making their low gear set for the 4L80E. I had one of the 2.75/1.57 sets in and it worked great although I kinda wished I had sprung for the 2.97 one. I had almost the acceleration of the 4L60E without the weakness of elderly hamsters and rubber bands. Plus, the 1-2 drop was about right. The 2.97 would have better acceleration, but the 1-2 drop is pretty close to the 4L60E drop. If you could find anyone that still had one available, that plus the Gear Vendors unit would make a nice setup. The gear spread with the low gearset plus the Gear Vendors unit would be quite a bit better than the plain 4L80E, and you could run a slightly higher (lower numerically) rear gear and get the same takeoff you have now with better mileage, or keep what you have and have a better takeoff with better but not quite as good of mileage as with a plain 4L80E and no GV.

Transmission Center (https://transmissioncenter.net/shop/conversion-kit-2-97-4l80e-6-speed-conversion/) claims to have a 2.97/1.57 one but I'd verify it's correct.

[peterwollman]

I reached out to Jake regarding the Engine Breaking issue on the TCI 6X and whether or not the valve body could be modified to do Engine Braking or if a PCS VBM-2000 4L80e 6-speed valve body was available could work with a TCI 6x to give braking in the electronic shift mode or any other options. He basically wouldn't touch the issue on the 6x, and said just to return it to TCI. I don't believe he thinks much is good about the TCI 6x. I am surprised that PCS used to make a value body with engine braking in the electronic shift mode and apparently TCI was preparing a VB to do the same and now it seems that no one knows anything about it? I am not that knowledgeable about automatic transmissions and was hoping that the 6x would be the way to go for my car, but that was based TCIs advertisements, manuals, and techs before I bought it. The TCI 6x seems to perform well enough but the lack of Engine Braking is a real problem in a road car. Maybe I should have never switched to an automatic, but I thought I could have the best of two worlds. Before I give up and return it, is there anyone or a company out there that knows how to provide Engine Braking in the electronic shift mode?

[scottsdaletrans]

I have a lot of insight about the 6 spd 4l80e. Gm originally created a 6 spd 4l80e prototype in early to mid 1990’s. The engineer that built it left GM and took a job with PCS at some point. TCI had hired PCS to consult on an unrelated project and the engineer told TCI about the 6 spd 4l80e. I believe TCI contracted PCS to show them how to do it on the context TCI would be buying controls and wiring harnesses from PCS. TCI then went with computers and harnesses from a different vender. I believe PCS did sue TCI. The only reason PCS started selling the 6 spd valvebodies and computers was to stick it in TCI’s eye.