Well, I finally got the 4.88s and the TrueTrac put in my truck. Running 35s still. Definitely notice the rpm difference and it seems to get up and going faster.. I still am curious of why I don't have tons of "take-off" power. So I think it may be in my transmission..

RPMs are with OD off 60mph at 2,900rpm and OD on 60mph at 2,000rpm so I don't see how some of you all run interstate with OD off and 4.88s cause going 70+ would put them RPMs WAY up there.

I guess it's normal to shift at 3,500rpm with OD off and on cause that's where mine shifts. Wish it shifted right near the red line instead of 3,500.

I'm not romping on it but when I go to pass people, it still works the truck a good bit. It does get up there faster. I know my tranny slips when I pass people once in awhile so I don't know if that's it or not... I can be going 60mph and smash it and it'll bounce off the limiter. Doesn't do it all the time but it does it once in awhile. I'm probably gonna get a trans cooler kit one day to help the temps.

There is one thing I had a question about... It was making this horrible squealing noise when I was near home yesterday in a parking lot. It did it at low speeds when I was turning real sharp. I went home and jacked it up cause it sounded like it came from the rear left wheel. Took wheels off and put back on. Now it doesn't make the noise anymore.. Hmm. I figured it could be the TrueTrac on the asphalt/gravel but I wouldn't think they would make that noise.. I'm still in the 500 mile break-in process the guy told me to do for the gears. He mainly just said no burnouts.

I would love input from guys with 4.88s on this. And some other knowledgeable people on transmissions. I really hate to rebuild it already.. Maybe the bands or something just needs adjusting? TV cable was alright when he checked it about half a year ago. The dang thing has been babied all it's life. I never had the fluid/filter changed in years so could that be a culprit?

All you guys' help is appreciated. And for whoever didn't see in the General Section, I'm not running my SCT anymore until I get Flyin Ryan's tunes. People's been saying problems about Hemifever's tunes. I didn't even notice a difference anyway from stock to the 93 tune so.

 

Wonder if you aren't experiencing the pressure sensor problem these transmissions have at large throttle openings...... tends to hold the gear FAR longer than it should.

Still the original electronics in your trans? Last time fluid/filter was changed?

 

Where is the sensor at? I know someone else mentioned something like that too on another forum.


And yeah, I even put the SCT programmer back to stock until I get better canned tunes. The canned tunes I got from Hemifever seems like nothing has changed in performance/mpg wise.


ANDDDD the filter and fluid was probably last changed 4 or so years ago.. I know. Could that be some of it?

 

Sensors and such are right above the filter. You can get 'em both for around 100 bucks. Get the Borg Warner heavy duty solenoid.... you can find them on ebay from various sellers. Change the fluid and filter too. (like you would get a choice. )

 

I had a guy that works on mustangs drive it an hour ago...


He said to start with putting new tranny fluid in, a new filter, and adjust the bands since I haven't in years. I'll have that done when my diff fluid gets changed. He said to him it seemed real nice but he could feel what I was talking about.


But do you think I should just start with that or go ahead and get the sensors? This wasn't gonna be part of the build till next year. I got a lift and bigger tires to go yet this year.

 

Sensors are another 100 bucks, along with fluid and filter. They are almost what I would consider a 'maintenance item' on high mileage trucks.

 

I'll look into them. It only has 135,000 miles on it, but it wouldn't be a bad idea to get em replaced! Thankya man!