4th/OD Switch??
#16
Tim is thinking it's something screwy with the TPS, and a 98 12v I'm working with him on some other tweaks to my tranny, so one way or another, we'll get it straightened out!
I'm sure it's something simple that my limited Auto knowledge is amplifying
Chris
#17
Mine does the same thing, it downshifts into third gear while locked up. I'm pretty sure it's the way the VB is setup because I had Dave build me one that locks in all forward gears. But if I come to a stop with the switch on it doesn't unlock, that's for sure
#18
#19
Yes, relay came up missing.
Tim is thinking it's something screwy with the TPS, and a 98 12v I'm working with him on some other tweaks to my tranny, so one way or another, we'll get it straightened out!
I'm sure it's something simple that my limited Auto knowledge is amplifying
Chris
Tim is thinking it's something screwy with the TPS, and a 98 12v I'm working with him on some other tweaks to my tranny, so one way or another, we'll get it straightened out!
I'm sure it's something simple that my limited Auto knowledge is amplifying
Chris
I know old joke...
Hooking up a pressure gauge should tell you pretty quick on whats going on. When you throw your lockup switch, the governor pressure should go all the way up, and it should stay up as long as it's locked up. If the pressure is up, and your torque converter comes unlocked, then it's probably a problem in the valve body. If the pressure drops and it comes unlocked, while the switch is still on, then it most likely is a electrical problem, such as a governor pressure solenoid, or governor pressure transducer.
Paul
#20
Awww.... I see the problem now! You're missing 12 valves!
I know old joke...
Hooking up a pressure gauge should tell you pretty quick on whats going on. When you throw your lockup switch, the governor pressure should go all the way up, and it should stay up as long as it's locked up. If the pressure is up, and your torque converter comes unlocked, then it's probably a problem in the valve body. If the pressure drops and it comes unlocked, while the switch is still on, then it most likely is a electrical problem, such as a governor pressure solenoid, or governor pressure transducer.
Paul
I know old joke...
Hooking up a pressure gauge should tell you pretty quick on whats going on. When you throw your lockup switch, the governor pressure should go all the way up, and it should stay up as long as it's locked up. If the pressure is up, and your torque converter comes unlocked, then it's probably a problem in the valve body. If the pressure drops and it comes unlocked, while the switch is still on, then it most likely is a electrical problem, such as a governor pressure solenoid, or governor pressure transducer.
Paul
Actually, I need to drive it tonight and narrow down the problems for Tim...it might be a PCM problem!
Thanks for the tip, though!!
Chris
#21
Same set-up as Paul in my truck. Once locked it stays locked until I close the tc clutch switch and the OD switch.
#22
Well, we've figured out I got lucky again. I guess some PCM's will downshift even locked up, while under 1800RPM. I got one. I never noticed it not unlocking after 1800RPM because of the 35's. At 1800+ I'm over 80mph, and I rarely run that fast
So I'll just be wiring a switch for forcing 4th gear, and use it when dynoing...that's really the only time I care about lugging 4th gear
Chris
So I'll just be wiring a switch for forcing 4th gear, and use it when dynoing...that's really the only time I care about lugging 4th gear
Chris
#26
Well, my truck is currently running without a PCM. So, I have BOTH my lock-up and OD on toggles... I love it cause I can shift outa OD when I'm going 50 behind ol' granny, build a lil boost and about the time I'm pulling out around i flick in OD and my truck just launches like a monster (Rather than slowly coming alive as the turbo first lags then slowly builds some boost). It's pretty simple though; just two wires that you have to splice into and take to ground individually.
As far as the downshift your DTT VB probably has the passages drilled out so it can lock up in 2nd and will downshift if you mash it... I like the way the trans-go kit makes my tranny semi manual as it will hold any gear unless I slam on the brakes or pull it down with the selector
As far as the downshift your DTT VB probably has the passages drilled out so it can lock up in 2nd and will downshift if you mash it... I like the way the trans-go kit makes my tranny semi manual as it will hold any gear unless I slam on the brakes or pull it down with the selector
#29
Several years ago I installed a 3-position switch in my '98 to manually control both the OD & lockup solenoids... made driving the truck much nicer (just switched both circuits to ground IIRC).