Had this tranny built by local shop, it had been back to him twice and I've given up . Overdrive has yet to work, he thinks its something to do with the line pressures not allowing it to shift . Also it shifts out of 1st at 20mph even though I have shifter in first and it doesn't kickdown. It will stay in 1st if shifter is in 1st and pedal is mashed to floor, I played with the kickdown and it doesn't seem to make a difference. Can anyone help here? The guy said he would look at it next week but I think I'm better off figuring it out myself if its possible.
518 short shifts and no od
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TrailBeast
AKA Mopars4us on Youtube
Line pressure is easy to chk, and it's easy to fix if he halfway knows what he's doing.
Low line pressure can cause a no shift (as in a major internal hydraulic leak)
I would think the shifter may be WAY off and you are not actually in 1st but manual second.
This would be pretty obvious though when you go to park and it won't travel that far.
It almost sounds like it has the wrong manual valve in it.
Maybe Tracy, Fishy68 has an idea?
Low line pressure can cause a no shift (as in a major internal hydraulic leak)
I would think the shifter may be WAY off and you are not actually in 1st but manual second.
This would be pretty obvious though when you go to park and it won't travel that far.
It almost sounds like it has the wrong manual valve in it.
Maybe Tracy, Fishy68 has an idea?
BigBlockMopar
BigBlockMember
Learn to adjust the kickdown-linkage properly. Wrongly adjusted, it can kill the transmission in very short order.
To get a baseline adjustment, adjust the kickdown linkage so you can 'just' slide it over the pin at the throttle-linkage, when both are held at fullthrottle-position. (throttle fully open and kickdownlinkage pushed all the way to the rear).
Take the car for a drive and see if the shiftpoints are happening at 'normal' rpms.
Finetune the kickdownlinkage if necessary.
Then test the OD-function and re-adjust the shifterlinkage.
Do you have a carb on the car with original Mopar-linkage, or carb with a modified GM-linkage?
To get a baseline adjustment, adjust the kickdown linkage so you can 'just' slide it over the pin at the throttle-linkage, when both are held at fullthrottle-position. (throttle fully open and kickdownlinkage pushed all the way to the rear).
Take the car for a drive and see if the shiftpoints are happening at 'normal' rpms.
Finetune the kickdownlinkage if necessary.
Then test the OD-function and re-adjust the shifterlinkage.
Do you have a carb on the car with original Mopar-linkage, or carb with a modified GM-linkage?
TrailBeast
AKA Mopars4us on Youtube
Try backing it off so it has more slack.
Shifting into 2nd at 20 under normal throttle conditions is adjusted pretty tight.
This could also cause OD to never come in.
It won't have anything to do with shifting into second when in manual low though.
Shifting into 2nd at 20 under normal throttle conditions is adjusted pretty tight.
This could also cause OD to never come in.
It won't have anything to do with shifting into second when in manual low though.
ive been trying to educate myself on these trannys. there's alot of talk about the governor. my tranny has some diesel internal, i'm not sure on what exactly but i know the od unit is diesel and valve body is gas, is it possible the wrong governor was used and could cause this?
TrailBeast
AKA Mopars4us on Youtube
The tighter the cable, the later the shifts.
I was thinking you might have it so tight that OD will never come on because most TF transmissions shift into second way before 20. (Stock without a shift kit anyway)
I know the springs are different, but don't remember how.
This wouldn't cause the second gear shift in manual low, but it very well coud cause shift point issue's. (it's possible)
fishy68
Tyr Fryr's Inc.
What's the engine? Diesel or gas? If it's a gas engine it's the right governor.
Are we talking about a early A518 or late 518? The later version (I think started in 96) has some electronic sensors inside that talk to the computer.
It is a smallblock gas, it is the early 46rh non lockup
fishy68
Tyr Fryr's Inc.
Governor should be right. I haven't ran into any problems like your describing but I also haven't done much work on 518's. Make sure the throttle pressure linkage is adjusted correctly like described above. If it is and it still doesn't shift right something's screwed up in the valve body. Maybe the rebuilder put something in wrong or left out a check ball. Did he install any type of shift improver kit?
If it is a non lock up unit you need the 2 wire connector just behind the manual linkage hooked up for overdrive.
The 1-2 shift is correct at 20 mph at light throttle an 3rd should be about 30 mph or so.
If you let it shift from 1-2 then mash the throttle to the floor it should down shift to 1st gear at low speeds like 25 mph.
If it is shifting 1-2 every time you take off from a stop it is not the governor.
How do you have the overdrive wired up?
The 1-2 shift is correct at 20 mph at light throttle an 3rd should be about 30 mph or so.
If you let it shift from 1-2 then mash the throttle to the floor it should down shift to 1st gear at low speeds like 25 mph.
If it is shifting 1-2 every time you take off from a stop it is not the governor.
How do you have the overdrive wired up?
he installed a transgo 2 kit
yes it is a two pin connector, it short shifts even with 3/4 pedal, the only way it won't is if i hold in first and wot wich would be fine but i hate the way it will shift under light throttle even if i'm in manual low.
i have 12v going to one wire and a toggle switch breaking the ground on the other wire.
how much range should my cable have? when it is set so that it barely comes tight at wot it has some play at idle.
thanks guys for your help here .
fishy68
Tyr Fryr's Inc.
OD wiring sounds ok. On the throttle pressure adjustment, are you saying that when at WOT the cable is pulled all the way, then when the throttle is at idle there's some slack in it? If so that sounds ok too. One mistake I see some guys make when installing a shift kit is they install the sleeve on the throttle valve backwards. It'll fit either way but if you put it on backwards it holds the valve in about 1/2 way even at idle. That causes late upshifts. I haven't seen it happen on a 518 but it's possible because the throttle valve is the same design and I imagine on a 518 it'd also cause it to not want to go into OD.
The rear gear selection maybe giving you a problem if you have steep gears like 4:10's 4:56's etc,it will up shift quicker than most stock 3:55 in most trucks.
If your not getting a down shift your pressure is to low(after reading the first post).
Raise the line pressure,if the line pressure is to low it will also have no overdrive.
If you drive it slow upon a 1-2 up shift it should drop down to 1st when you floor it,if it does not your t.v pressure is to LOW.
If you disconnect the t.v your upshift times should be different from when it connected,if does not change you have a problem in the valvebody like fishy said.
If the t.v makes no change to the transmission performance try another valvebody(without the shift kit)
The overdrive problem could also be a bad solenoid,you may have more than one problem.
If your not getting a down shift your pressure is to low(after reading the first post).
Raise the line pressure,if the line pressure is to low it will also have no overdrive.
If you drive it slow upon a 1-2 up shift it should drop down to 1st when you floor it,if it does not your t.v pressure is to LOW.
If you disconnect the t.v your upshift times should be different from when it connected,if does not change you have a problem in the valvebody like fishy said.
If the t.v makes no change to the transmission performance try another valvebody(without the shift kit)
The overdrive problem could also be a bad solenoid,you may have more than one problem.
i'm having problems with shifting early.
I did try adjusting the way you suggest but my tv cable becomes tight before throttle is in wide open position.
You might have to change the position of the cable so it pulls from the idle position to wot.
The throw on the carb or t.v lever needs to be adjusted so when you step on the throttle the cable moves from idle to wot.This needs to be done first before you can adjust the line pressure properly.
Most of the time the problem is on the carb linkage,might have to move it closer to the center shaft of the carb for less pull on the cable,if it is to far to the bottom it will pull the t.v to quick binding the cable.
Try pulling the cable out and clamp it to raise the line pressure to see if it changes,leave it disconnected from the carb,the farther you pull it the later the shift,like I said before if this makes no difference it is in the transmission.
The throw on the carb or t.v lever needs to be adjusted so when you step on the throttle the cable moves from idle to wot.This needs to be done first before you can adjust the line pressure properly.
Most of the time the problem is on the carb linkage,might have to move it closer to the center shaft of the carb for less pull on the cable,if it is to far to the bottom it will pull the t.v to quick binding the cable.
Try pulling the cable out and clamp it to raise the line pressure to see if it changes,leave it disconnected from the carb,the farther you pull it the later the shift,like I said before if this makes no difference it is in the transmission.
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