Engine/Transmission (1998.5 - 2002) mystery switch

[Mtngoat]

Can someone please explain a mystery switch? I've searched on it, but didnt really get the answers I wanted. What does it do, exactly, and is it a good thing??



Robin

 

[pwr2tow]

Short answer, it's a $1. 50 toggle switch used instead of spending two- three hundred dollars on a controller box to lock the torque converter.



Controller box has more functions and you don't have to remember to turn it off manually like you do with a mystery switch.



Ron

 

[Bob Wagner]

if used incorrectly a mystery switch can be the most damaging item you can add to your transmission.

 

[Mtngoat]

Bob,



Yep, that was my question, the pluses and minuses of the thing. A TDR member here in my area has one and swears by it. Incidently his truck was stolen last Friday morning! He was gassing, left it running and after coming out from paying , it was going down the street! As of last night, it's still missing.



Robin

 

[Bob Wagner]

sorry to hear that Robin, was it a tdr member?

 

[Mtngoat]

Yep , Dennis Garrett, real nice guy!!!! Says he wants his ol 12 valve back, but if it doesnt turn up he'll break down and buy a new one!



Robin

 

[Bob Wagner]

OUCH Dennis has been a member for a long time

 

[Silver]

My buddy has a variable pitch TH-400 in his '78 Trans Am. I wired it up to a lighted toggle switch. When the torque converter is fully engaged, the light is on. This helps him remember to turn it off when he gets out.

 

[Boldt's Wagon]

For a mystery switch that will not tear up the transmission if you try to stop without remembering to turn it off:



https://www.turbodieselregister.com/forums/showthread.php?s=&threadid=54464&highlight=goofproof

 

[SteveE]

Mystery switch revealed

I just happen to have a BD Torqloc mystery switch.

Autoloc system Part # 103029" Automatic engine brake and lock-up clutch control system.

It worked great on the ol '98 CTD w automatic trans.

Unlocks automatically when engine speed goes below 25 mph, prevents damage to torque convertor and keeps engine from lugging.

 

[HVAC]

Dennis Garrett

That's terrible news about Dennis's truck!



Dennis is from Eudora Kansas I believe.



He's our resident train expert.





I beleive the genesis for the mystery switch was to aid use of E-brakes. If you don't have the TC locked on a long down hill, you WILL roast your trans. Too much heat develops from the TC slipping. All the switch does is complete the ground circuit to the trans which will cause the TCC to lock, as long as you have the relay jumped. The new controllers out are the way to go now.

 

[Mtngoat]

HVAC-



Your starting to answer my question, is the mystery switch a good thing or bad?? Or should I spring for the Smart Controller DTT has?? I just dont want to burn up my new transmission cruising around the Rocky Mountains with the Jeep and gear on the trailer behind. Sounds like (from Dennis) the mystery switch works fine, its just a little more manually operated than the controllers. I don't know. .



Robin

 

[HVAC]

Mystery Switch Good/Bad???

Glad I could clear this up for you Mtngoat



I personally prefer manual controls. My auto has a manual valve body so I can control shift points. I have manual controls for OD and lock up. My transmission works right every time, cause I control it.



That being said, most folks are using the controllers to do the work automatically. The ones I have installed work well enough.



So, is the mystery switch good or bad??? That's a personal preference thing.



I have to say the negative conotation is from those that would use the mystery switch to lock the TCC to aid acceleration. This can put your input shaft in jeopardy. Hence the need for the billet input shaft.



IMO, the mystery switch is not a bad thing when used responsibly. The alternative without any lock up mechanism ( a fried transmission) is a much worse result.