Thread: Help me ID if this is a trans slip or not

I have notice over the past month or so, I'll be driving normally, not even fast. Where I'll feel what Im not sure is a slip or not. I'll be as detailed as possible. Lets say I'm doing 70mph on cruise control. I'll give it just a lil bit of gas to pass another car, no more than 5-10% throttle most days. At 70mph im usually at 2400-2500 rpms cruising and its jump a few hundred rpms for a sec and feel a slip or a small "thud", but then continue to accelerate normally. I look at my scan-gauge to see that i'll be at 20-30% throttle when this will happen. This is only at around 70 mph. Also this isn't every time, it is very inconsistent. Other than that, the car drives fine and typically shifts nice and smooth. From 0-75 mph at 30-40 % throttle she'll shift fine all the way through. Just a lil background, in February, I had a new 4th gear clutch shaft installed. Has driven fine since. Since I don't know exactly what it is, I've been rather gentle with the car so I don't cause more damage or speed up whats already going bad. I'd guess its a trans issue, but I figured i'd get some other opinions too.

It might just be the torque converter unlocking.

Originally Posted by Fivefingerdeathpunch

It might just be the torque converter unlocking.

huh...I didn't even consider that...good point. Eventually Im going to have a buddy of mine scan it, bud he's a couple hours away

Originally Posted by Fivefingerdeathpunch

It might just be the torque converter unlocking.

Agreed

Originally Posted by lsxftw

Agreed

Would there be a code I could ID this by?

No code for a torque converter...it normally locks and unlocks based on what you do to the pedals.

Easy way to check if it's the TC. Drive normally w/o cruise. RPM should settle in after a moment or two. Lightly touch the brake pedal with your left foot while keeping your right foot steady on the throttle. Just enough to make the brake light come one (the pcm see's that switch open). Your rpm should raise slightly when you do this.. this is the TC unlocking. Once you let off the brake, the rpm should settle back down, aka TC relocking.

This is normal operation. The TC is programmed to lock/unlock based on events.
You let off throttle - Unlock
You add X % throttle - unlock
You touch the brakes - unlock
You cruise fairly consistenly - lock
You reach x speed, throttle % and X load - lock