Tuner recommended overfilling tranny to help shifting with a big stall
#1
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From: wentzville, MO
Tuner recommended overfilling tranny to help shifting with a big stall
Ive got a 3800 edge stall in a tranny that had all the servo/clutch pack upgrades a few years back will shift fine on the street, but at the track it will just lightly touch the revlimiter before shifting.
My tuner recommended I overfill my tranny fluid to combat this.
He said the bigger stalls will leave the pan dry under hard acceleration so a little extra fluid will fix that.
I tried searching and couldn't find anything on this
My tuner recommended I overfill my tranny fluid to combat this.
He said the bigger stalls will leave the pan dry under hard acceleration so a little extra fluid will fix that.
I tried searching and couldn't find anything on this
#6
your stall is most likely a lot smaller than the original one so it takes just a little less fluid not more. He needs to play with wot shift speed/rpm to account for the slip of the stall to get it to shift when desired.
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#8
Yep i have no idea what im doing to the people who say find a new tuner. I've heard for years people converters sometimes needing to overfill the trans by a 1/2 or little less.
https://ls1tech.com/forums/automatic...2-qt-okay.html
Check 2nd post down.
Ths reason i suggested this to James i use a very nice 4l60e calculator that uses tire size/stall size/gears and rpm to calculate shift speeds and so on.
Now i have done a had full of builts Transmissions by a certain local builder who is VERY good with the 60es and wit this calculator everything is SPOT on!
I almost use this to see if the trans is in good working order, i get older transmissions or worn out ones where i will have to keep adjusting the mph and speed down on the 2-3 to get it to shift correctly(usually a sign of a weak transmission)
For example with the OP cars, its a baby cam 3800 stall car with a transmission that had a little work done a year or so IIRC. Now on his car i have it commanding the shift at 6k and a certain mph(which is a few already below the suggested shift mph) and i tuned the car a week ago and shifted correctly and everything went well. Now at the track this past weekend he said he was having issues with the limiter on the 2-3 so i suggested checking trans level and i have heard and also practiced in my 6l80e in my g8 overfilling a little bit to see if that helped with it at all. If not he needs to start looking at trans issues.
https://ls1tech.com/forums/automatic...2-qt-okay.html
Check 2nd post down.
Ths reason i suggested this to James i use a very nice 4l60e calculator that uses tire size/stall size/gears and rpm to calculate shift speeds and so on.
Now i have done a had full of builts Transmissions by a certain local builder who is VERY good with the 60es and wit this calculator everything is SPOT on!
I almost use this to see if the trans is in good working order, i get older transmissions or worn out ones where i will have to keep adjusting the mph and speed down on the 2-3 to get it to shift correctly(usually a sign of a weak transmission)
For example with the OP cars, its a baby cam 3800 stall car with a transmission that had a little work done a year or so IIRC. Now on his car i have it commanding the shift at 6k and a certain mph(which is a few already below the suggested shift mph) and i tuned the car a week ago and shifted correctly and everything went well. Now at the track this past weekend he said he was having issues with the limiter on the 2-3 so i suggested checking trans level and i have heard and also practiced in my 6l80e in my g8 overfilling a little bit to see if that helped with it at all. If not he needs to start looking at trans issues.
#9
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From: Turnin' Wrenches Infractions: 005
Changing fluid levels changes shift pressures. And that's a fact. Going low on fluid changes them more drastically then going over. But, there is still no concrete reason to run more fluid then full.
And, kinda hard for people to not jump on the bandwagon when OP clearly states his car is on the limiter. Seriously, how long does it take to bump a mph and/or rpm table down a touch?
And, kinda hard for people to not jump on the bandwagon when OP clearly states his car is on the limiter. Seriously, how long does it take to bump a mph and/or rpm table down a touch?
#10
It's not like i havent tuned a TON of local fbodys and a few 10 second NA 4l60e cars....
#11
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From: wentzville, MO
In 04blackgmc's defense it shifted great while he was tuning it earlier in the week. It wasn't till we got to the track that it started touching the limiter and gmc's gf's car broke an axle that night so he was a little busy and this suggestion was over the phone the next day.
#12
the trans fluid was probably a bit hotter the night of the track so you had more slippage from the converter causing you to bump the limiter.
i use the bluecat calculator and it is usually very close, but there are too many variables in each trans/converter/car to use them as concrete settings.
i can see overfilling by a touch, but not because the pan is running dry because of a converter.
i use the bluecat calculator and it is usually very close, but there are too many variables in each trans/converter/car to use them as concrete settings.
i can see overfilling by a touch, but not because the pan is running dry because of a converter.
#13
Ths reason i suggested this to James i use a very nice 4l60e calculator that uses tire size/stall size/gears and rpm to calculate shift speeds and so on.
Now i have done a had full of builts Transmissions by a certain local builder who is VERY good with the 60es and wit this calculator everything is SPOT on!
.
Ron
#15
I think overfilling the 4L60 has caused foaming of the fluid as the oil gets whipped by the rotatating parts instead of having a gap between the oil level and the rotating assembly. I have heard of people switching to hygard or tractor trans fluid to lower the stall a few hundred rpm.
#16
Just a thought but.........My car will occasionally bounce off the rev limited on the 1-2 shift. If the car sits in the lanes running for at least 4-5 mins then it's fine but If I get rushed to the line and the car doesn't run long enough then it'll hit the limiter. I'm not sure if this is in the tuning or in the trans but just thought I'd share........Level 2 Performabuilt btw
#17
Dont Overfill your trans!!! The tuner needs to adjust the **** & make it right!! Every car/truck is a little different! Even from the Factory Clearances arent all exact, They Vary LMAO Come on dude REALLY!!!!!!!!!
#18
I guess i was doing it wrong for years overfilling my 6l80e and going mid 10's on stock transmission.
I forgot over the internet everyone knows everything..
#20
And yes i use the bluecat calculator. I can always tell when a trans is in good working order with it when everything is spot on. I will have to leave the rpm down and mph lower than the calculated when i have issues with cars tapping the limiter and or shifting too high.