natronathon

Just took the car out for a spin, and had had some shifting problems that i've NEVER had before. Under WOT the car dropped from 2 to 1 and accellerated fine and then shifted losely into 2nd, then when shifting into 3rd, hit the rev limiter and wouldn't shift until i took my foot out of the gas... What might be causing this? The only things i have done to it, are I have had the tranny fluid changed and flushed, I installed a new transmission mount, and replaced the rear end fluid. The tranny fluid change and flush was done at a shop, I installed the mount and changed the rear-end fluid. There was no clunk or hitting sound. I just felt like the transmission was having a hard time shifting. There have never been any symptoms of this before. You help and ideas would be greatly appreciated! Thanks in advance for all the info!

Nathan

natronathon

just used hp tuners to check the temp and it was at 252 degrees!!! isn't that way too hot???? I only drove it like 5 miles, and only went wide open once! it had been standing still for over 24 hrs!!!

1999Z28

you just had your transmission flushed before this??
if so, it probably was getting ready to go out anyways and now the flush took the old gritty fluid out that was allowing the clutches to grab and they won't grab with new fluid.

natronathon

yeah the transmission was flushed about 2 weeks ago. But, i haven't had any problems with it shifting since then. Im just suprised at how hot it got within a max of five minutes of driving... its incredible... Now i have to come up with 2000 for a new transmission...

does anyone think it could be a problem with the tranny cooler? a stock transmission shouldn't get that hot with a working cooler, should it?

natronathon

help!

natronathon

i just made another test run, and the results are positive/interesting...

First off, the car shifted near perfectly, very firm, and the transmission never got about 135 for the whole trip. Also I took the exact same route as i did last night. Could it be a fluke? or do these transmissions sparatically slip when they are going bad? Im confused... any input would be appreciated...

pSSycotic

iTrader: (7)

i have a stock tranny witha b&m 24k cooler...when i drive around reg in 80 degree houston weather it stays around 140ish...when racing it gets to about 160ish...id have urs checked out 252...either somethin was reading wrong or your ****** up your tranny

RevGTO

iTrader: (12)

I hate to suggest the obvious, but did you personally check the fluid level according to the proper procedure after the flush? How many miles are on the car? Did you ask the shop about the appearance of the old fluid and if there was anything in the pan?

Red Heartbeat

iTrader: (9)

If you got the fluid that hot, I'd drain and refill it with fresh clean fluid. Do you have a stall converter? I had a similar problem and ended up having to rebuild the transmission because 3-4 clutches fried. I disabled P0757 and P0751 in HPT after rebuilding the transmission. I run a Vig 3600 stall and all is good now and it shift nice and solid. I replaced the old style 1-2 and 3-4 shift solenoids to the newer filter type models while I was at it. The solenoid update was suggested by all builders I talked to.

natronathon

I checked the fluid level, and it was normal. I dont know if there was anything abnormal in the pan...


What i dont understand about the whole process is these two thing:

How could the transmission reach 250 degrees at midnight when only driving 5 miles, only about 30 seconds of which was under moderate to high power???

How could it be that today I had absolutely no issues with it? I took the same route, floored it for the same amount of time and everything....

Could it be a computer issue?!?!?

TopFlite

Interesting. Does this allow for firmer shifts?

Natronathon, I just had my trans. rebuilt after having a problem like this. Not only would it bounce the limiter from 2-3 shift, but would also slip at the same time when shifting part throttle. Turned out, 3-4 packs were fried, as well as 2-4 bands. Have a rebuilt trans now and i'm heat cycling the crap outta it.

monicaz28

iTrader: (5)

When they're going out, they do sporadically slip sometimes.... the weather could be a major factor between results in the 2 different times you took it out. Was it the same, or was it cooler when you took it out the second time?
Your tranny is probably going to need a rebuild if it's beginning to slip. Mine took over 2 months to finally give up. It really shouldn't be all that much to put some new clutches and bands in a stock tranny at all. You can buy a bad *** built tranny with warranty for $2k.

natronathon

where can you get a built tranny for that price? Also, it was warmer the second time i went out...

monicaz28

iTrader: (5)

Rock-On Transmission does it for that price... or $2200.

chris718

a scan tool can quickly isolate a slipping clutch by monitoring the input and output speeds and shift commands of the ecm to the solenoid valves and how long it takes for them to respond.usually after a good run a speed ratio error code will surface indicating a slipping clutch.loss of output shaft signal(the transmission uses this info for shift scheduling)can also cause this problem without setting a code.using an ohm meter to check the resistance of the output speed sensor can be of great help and is very easily done at home.

natronathon

can this be monitored through Hp tuners at all? if so how would i go about doing it ?

Luna

iTrader: (6)

I'm actually having a very similar issue right now. I am going to go to autozone tomorrow to see if any codes have been set.

https://ls1tech.com/forums/general-maintenance-repairs/486293-why-did-i-visit-rev-limiter.html

Let me know what ends up happening with your trans.