6R80 with EEC-IV/EEC-V

Anything not covered in the other forums.
Slow94
Posts: 81
Joined: 2021 Mar 23, 19:59
Location: Moncks Corner SC
Vehicle Information: 2004 ford lightning: built motor, built trans kenne bell 3.2, nitrous
Best 1/8 mile: 5.92 @ 113.4 all boost.
1994 ford lightning: 427w twin 67/67's.

Re: 6R80 with EEC-IV/EEC-V

Unread post by Slow94 »

decipha wrote: ↑2025 Jan 13, 22:07 you can always use a 6r ecu to just control the trans no problem, same as the 4r and 6r people have done for years with 2 ecus.

im not sayibg the 10r is a bad trans but theres little to no benefit swapping from a 4r for the 6 or 10.

What same version vehicles are you referring to ?
Mustang and f150's specifically with coyotes. The coyote makes terrible torque but sure does like rpm. There is a very large performance gap between 2nd gen coyotes and 3rd gens. That isn't due to the few more HP. The 10 speed makes a huge difference in performance. I keep up with the Ford truck scene the most and the 10 speed trucks are miles away from the 6 speed trucks with same mods or HP levels. Heavy trucks that make little torque need the gearing to get moving and all the extra gears to keep it high in rpm range where the coyote makes power. For reference my buddy had a 2016 and 2018 rcsb coyote truck both with blowers and E85. Similar boost numbers the 2nd gen would run 6.6's in the 1/8th and the 3rd gen would run low 6's. It was quite literally a half second quicker with similar mods and actually a heavier truck. Now there is a limit to where the extra gears become a hindrance, but that comes well over 1000 rwhp. Usually that is when strength is prioritized and it's more simple to run a conventional 3 speed. Both the 6r and 10r have a useless 1st gear ratio with high horsepower so that makes the 6r left with 3 forward gears just like the 4r... The 10r however has 6 forward gears that allows coyotes in particular to stay high in the rev range. Good trans tuning is a must though.
decipha
Posts: 7111
Joined: 2021 Feb 15, 12:23
Location: Metairie, LA
Vehicle Information: 2x '19 PU Explorer Sport 3.5L Eco's AWD

Re: 6R80 with EEC-IV/EEC-V

Unread post by decipha »

Thats not a fair comparison as the gen 2 is 365hp and the gen3 is 435. Thats a 70hp difference all else being the same.

Even at the same peak power level the gen 3 will out torque the gen 2 across the board so thats not a fair comparison at all.

But thats all besides the point, the OP wanted to swap a 6r in lieu of the 4r I only mentioned the 10r as reference.
Slow94
Posts: 81
Joined: 2021 Mar 23, 19:59
Location: Moncks Corner SC
Vehicle Information: 2004 ford lightning: built motor, built trans kenne bell 3.2, nitrous
Best 1/8 mile: 5.92 @ 113.4 all boost.
1994 ford lightning: 427w twin 67/67's.

Re: 6R80 with EEC-IV/EEC-V

Unread post by Slow94 »

decipha wrote: ↑2025 Jan 15, 08:39 Thats not a fair comparison as the gen 2 is 365hp and the gen3 is 435. Thats a 70hp difference all else being the same.

Even at the same peak power level the gen 3 will out torque the gen 2 across the board so thats not a fair comparison at all.

But thats all besides the point, the OP wanted to swap a 6r in lieu of the 4r I only mentioned the 10r as reference.
For comparison a gen 2 2017 f150 has 385hp and the gen 3 2018 has 395.... They are very close. 10hp and 13hp difference between the gens there. I'm not comparing gen 1 and gen 3. All the fastest trucks out there are running 10rs unless it's a full on race truck. At that point a th400 or similar makes more sense. But I agree that I would just stick to a 4r as it's a beast of a trans. The 6r has no useful benefits over the 4r unless used for highway mpg and that will be negligible. The 10r if it could be controlled is best option for performance and mpg within a certain power range say stock to 1000 wheel HP or so. Again my experience is mostly limited to trucks so take that how you will.
Luis5.oh
Posts: 72
Joined: 2021 Mar 30, 12:27
Location: Culiacan, Sinaloa, Mexico
Vehicle Information: ---------------------------------------
*1995 Mustang GT - U4P0 - CBAZA
-95 Cobra manifold
-Siemens Deka 80's
-Explorer 4R70W (95 Mustang TCC Solenoid)
-Saleen racecraft lowering springs
-Moates quarterhorse
---------------------------------------
*2003 CTS base
-LS swap
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*2008 Mustang GT
-Coyote Swap

Re: 6R80 with EEC-IV/EEC-V

Unread post by Luis5.oh »

Then maybe because the cars with 6r and 10r are usually the ones with higher hp is why I feel them like better transmission
Sevensecondsuv
Posts: 139
Joined: 2021 Nov 08, 22:24
Location: North Central IL
Vehicle Information: 1995 F-250 RCLB with a built 300 and 4-spd running A1C
wbo2_aem_uego

Re: 6R80 with EEC-IV/EEC-V

Unread post by Sevensecondsuv »

Thanks for all the info guys. I'm glad to hear there are properly tuned 10Rs running around. The application I originally had in mind when I started this thread was 90s/00s trucks and panthers with relatively stock 200-300 HP engines. It seems the wider total ratio spread of a 6R would be a very nice improvement over a 4R for that range of HP/weight ratio vehicles.

Out of curiosity, how does running 2 ECUs work? How many other parts and inputs are required to get the 6R ECU to function? Does it require a CANbus? One issue I see is EEC-IV/V is mechanical throttle body while anything with a 6R is electric throttle. Can a 6R ECU actually control a trans without also controlling the throttle body? My understanding was the throttle body and transmission were both fully integrated into the torque management control strategy such that removing the throttle body from the equation would basically result in needing to rewrite the entire strategy.
Red2003XLT
Posts: 2
Joined: 2026 Apr 18, 16:22
Location: *`
Vehicle Information: 2003 Ranger XLT 3.0 auto 83,000 original owner

Re: 6R80 with EEC-IV/EEC-V

Unread post by Red2003XLT »

Hello All, just discovered this board and therefore getting an education. Anybody remember Pro-M Racing? They had develop a SCP to CANBUS decoder/interface to allow their ECU to communicate with the 2004 Mustang mainly the dashboard. I'm guessing other people have developed similar devices.

Also why no support for 07-12 Crown Vic? /4.6 2V 4R75? and 04-14 F150/E150 4.6 2V 5.4 2V - Books list 4.6 3V/5.4 3V as well I've never one in the junkyard
GrahamW78
Posts: 4
Joined: 2026 Oct 20, 06:11
Location: Berlin, Germany
Vehicle Information: 2005 Subaru WRX

Re: 6R80 with EEC-IV/EEC-V

Unread post by GrahamW78 »

red2003xlt mate welcome aboard, you'll get an education alright but the fees are paid in rabbit holes lol, i'm more of a points and carb man myself, my MGB's only network is me shouting at it from under the axle stands so pro-m racing is a bit above my pay grade, to be fair the missing crown vic and 2V stuff is definately one of those "somebody's got it working in a shed and never told anyone" jobs, anyway just my two pennies worth
GrazW_Leeds68
Posts: 6
Joined: 2026 Oct 21, 22:46
Location: Berlin, Germany
Vehicle Information: 2005 Subaru WRX

Re: 6R80 with EEC-IV/EEC-V

Unread post by GrazW_Leeds68 »

reckon i had a similar bother on an old bike rather than a car, red2003xlt. tried getting a modern digital dash to talk to a 90s ignition setup and it was a proper nightmare, ended up just binning the idea and running a basic standalone gauge, which worked sound and cost me alot less. never touched pro-m myself, so cant say owt about that decoder 👍
Cougar281
Posts: 107
Joined: 2022 May 04, 18:05
Location: St Louis, MO
Vehicle Information: 1995 Mercury Cougar
2002 PI 4.6L V8
1999 J-Modded 4R70W
2004 PTP2 PCM

Re: 6R80 with EEC-IV/EEC-V

Unread post by Cougar281 »

I will say this about the 10L90 in my CT6 - after the 'recall' was performed, its shifting kind of went to the birds. The shifts were no longer smooth, downshifts were often odd and clunky... So I found a TCM out of another 2019 CT6 with the same 3.0TT and per the VIN and TIS calibration lookup, had the same calibrations and the recall was still not performed on that VIN, and after copying MCVM data from the original TCM to the new one and changing the VIN to match my car in the new one, then running a relearn on the new TCM, shifts are back to being beautiful. They messed something up in that recall calibration.
decipha
Posts: 7111
Joined: 2021 Feb 15, 12:23
Location: Metairie, LA
Vehicle Information: 2x '19 PU Explorer Sport 3.5L Eco's AWD

Re: 6R80 with EEC-IV/EEC-V

Unread post by decipha »

My 2024 f150 5.0 10r80 work truck just turned 50k miles 2 weeks ago and has an ongoing trans issues. If you put it in drive and let off the brake it goes in to reverse and backs up an inch before going forward. I thought for the longest time it was just because my driveway is on a slight slant but a few days ago I was parked on a downward slant at a job site and when I put in drive it backed up and went up the hill in reverse a few inches before finally going forward. Caught me off guard to say the least.

I use the auto brake hold feature so I've always though I felt it but haven't really paid much attention to it and figured it was just the brakes loading. I've noticed it over the past year but just attributed it to my driveway being slanted. Not quite sure how long its been happening now.

Unrelated but figured someone here might know. My gauge cluster momentarily shut off and came right back on the first week I had the truck with only 100 miles on the odometer. I didn't think much of it and figured it did an OTA update. Happened again at 13k miles while driving down the interstate one day when I hit a bump. I figured something must have been loose, reported it to the fleet manager but nothing came of it since it didn't do it again. Well it just happened again about a month ago. Still not sure but I'm guessing its OTA updates. Anyone know for sure?
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