Reverse Lockout wiring for T56

[Papa t]

POWERTRAIN - Coyote Gen 3 with T56 transmission. Instrumentation GPS- Speedo

Trying to install American Powertrain Reverse Lockout module (ELUN-10013) and have a question on the VSS signal wire and VSS Reference wire. There are two wires in the FFR Harness Diagram label
(DR GREEN- SPEEDO SIGNAL) and (GRAY - SPEEDO SIGNAL RETURN). As far a I can see, these wires are not used ( open lines on the schematic) with a GPS speedometer. My question is, where does the lockout module get the VSS signal?

On my SLC, I have a wheel sensor for VSS signal.

Thanks

[Its Bruce]

The T56 has a VSS sensor. Your GPS speedo may also have a VSS output.

[Papa t]

No VSS output on GPS gauge.

[michael everson]

instead of using the module here is what I did. It's just a solenoid that needs 12 volts to activate. I ran a splice off the brake light wire that's going through the tunnel already and hooked it up to one side of the solenoid. The other side to ground. Now all you have to do is press the brake to activate the solenoid and go in reverse.
Mike

[Papa t]

Thanks Mike.

[edwardb]

That's the setup I have in my Coupe build -- T56 with the American Powertrain reverse lockout module and Speedhut GPS speedo. The connections couldn't be easier. Nothing required for the GPS speedo other than power and the antenna. The T56 has a VSS sensor installed. Plug in the two wires from the Ron Francis harness (assume that's what you have) to the T56 sensor and connect the other ends to the lockout module. Add power and you're done. Four seasons on the road and works perfectly. Reverse is only available when the vehicle is stopped and is totally seamless

[Papa t]

Just to confirm, there is no VSS signal required. The diagram from the module shows there is.

[edwardb]

Just to confirm, there is no VSS signal required. The diagram from the module shows there is.

Not sure how you got that from my post. Or others. Simple explanation:

GPS Speedo VSS: no.

American Powertrain module VSS: yes. Won’t work without it.

[rhk118]

This is a good post for me as have been thinking about wiring and similarly bought a reverse-lockout 'gizmo'. My T-56 came with this harness that was recommended: https://www.moderndriveline.com/shop/electrical-harnesses/ford-electrical-harnesses/3-in-1/tremec-magnum-all-in-one-harness-w-reverse-lock-out/ - Does it look like it will work for reverse lockout or will I need to go with Paul's solution above? I can use bluetooth to tell it what speed to lockout reverse and it gets the speed from the transmission, apparently. Can also calibrate VSS signals, whatever that means but I assume how the t-56 tells speed.

Looks like it will send a VSS signal from the transmission to tell speed? I assume that won't work with the GPS version of the speedhut speedo but theoretically I could buy a VSS one and not need to use GPS for speed?

I hope to look back at this post AFTER wiring and laugh at how little present me knows now about this stuff! Drill holes in aluminum and steel...advanced intermediate level. Wiring?....uhhhh....good news is I got a good price 2 years ago when I bought it than its current price...

[Its Bruce]

That will work for reverse lock out. The calibration of the VSS most likely means being able to adjust for diff ratio and rear tire size to get an accurate mph.

[edwardb]

This is a good post for me as have been thinking about wiring and similarly bought a reverse-lockout 'gizmo'. My T-56 came with this harness that was recommended: https://www.moderndriveline.com/shop/electrical-harnesses/ford-electrical-harnesses/3-in-1/tremec-magnum-all-in-one-harness-w-reverse-lock-out/ - Does it look like it will work for reverse lockout or will I need to go with Paul's solution above? I can use bluetooth to tell it what speed to lockout reverse and it gets the speed from the transmission, apparently. Can also calibrate VSS signals, whatever that means but I assume how the t-56 tells speed.

Looks like it will send a VSS signal from the transmission to tell speed? I assume that won't work with the GPS version of the speedhut speedo but theoretically I could buy a VSS one and not need to use GPS for speed?

I hope to look back at this post AFTER wiring and laugh at how little present me knows now about this stuff! Drill holes in aluminum and steel...advanced intermediate level. Wiring?....uhhhh....good news is I got a good price 2 years ago when I bought it than its current price...

Interesting module. Obviously, I don't have an experience with it, so take these observations FWIW based on only reading the information on the website. (1) I don't think you need to replace your GPS speedo. The module is providing the VSS output (in two different forms apparently) to be used for speedo and PCM if needed. But don't see how that's related to the reverse lockout process. Don't see where there's feedback to the module of actual vehicle speed. Which is based on calibration at the speedo. (2) It appears to act similarly to the American Powertrain module in that VSS pulses within a certain range are interpreted as low/no speed so the reverse lockout is switched. Looks like maybe that can actually even be adjusted within the app they describe. But it's not 100% clear to me. Bottom line, appears to me to be a replacement for the American Powertrain module. Would be easy enough to test. That's what I did with mine during the wiring process and confirmed it was working as intended. Be sure to report back your experience. Although at $400, not sure how many would choose that over the American Powertrain module if only used for the lockout. Good luck.

[Its Bruce]

Guys, the T56 provides its own VSS signal - that is the feedback to the module. All this module does is intercept that signal to determine when to ground out the reverse lockout solenoid to allow easy shifting into reverse. It seems strange to me that the Coyote ECU doesn't handle this issue on its own; it was literally a single additional wire for me to allow the GM ECU to function the RLO solenoid.

[edwardb]

Guys, the T56 provides its own VSS signal - that is the feedback to the module...

Right. That's what I (and others) described. If it came out otherwise, sorry.


It seems strange to me that the Coyote ECU doesn't handle this issue on its own; it was literally a single additional wire for me to allow the GM ECU to function the RLO solenoid.

Having installed both Coyote's and one LS3, agree there are differences it what is available between the two. Especially the crate version PCM calibration that most of us use for these Coyote builds. Ford has chosen, for whatever reason, to not provide everything available in the production PCM. Including vehicle speed for one. One isn't better than the other in my experience. Just different. It's an easy solution with the T56 and the American Powertrain module and potentially the Modern Driveline piece RHK118 is asking about.

Just had my Coupe with the Coyote and T56 out for potentially the last Tuesday night cruise of the season (:() and was again reminded how seamlessly the reverse lockout works when backing into a parking spot and again into my garage.

[Rian_Colorado]

I found a video on line that led me to this:

https://shop.bowlertransmissions.com/products/tremec-t-56-all-in-one-harness

This harness gets you reverse lockout, VSS speedo output with Bluetooth app to adjust output for multiple parameters, as well as an output for backup lights. The unit is VERY small, and is able to be mounted to the trans housing itself if you desire (ie - no more room taken up behind the dash etc. where most mount their reverse lockout.) Also space saving in not needing additional room for any GPS ant. for speedo. I'm also happier with a direct connection to the trans. for speedo output (won't go dead in tunnels etc. like GPS).

I thought the installation was easy and straight forward, and felt that having all of this functionality for <350$ was well worth it....

Rian

[rhk118]

Thanks Rian. Did you have to buy a different Speedo so work with that vss output?

[Rian_Colorado]

I actually used a completely different set of gauges from NVU (new vintage USA). I chose the Performance II gauges, and love them. Easier install I felt, and have all of the turn signal, hazard, CEL etc. all built into the gauge face, so no other wiring required for those items.191644

The piece from Bowler trans. actually has 2 different VSS outputs, and they are customizable, so I would bet that you could get it to work with any of the other gauge setups from FFR though.

Rian

[ChrisMiami]

Wow Rian - looks awesome! Can I send you my dash to do? 🤣