Sticking transmission

K8TEK · 12-08-2008, 07:49 AM

Greetings. I own a 2001 Olds Alero 2.4L with 98,000 miles on it.

The problem I have is when the car is upshifting, it seems to be sticking.

If I watch the RPM gauge, it will be at 3000RPM, then drop to 2500RPM, then 2000RPM. These steps are very well defined, it is not smooth like it should be. This happens when I am going between 35-40MPH.

Also, when I am on the highway traveling 60MPH, it will go from 2500RPM to 2000RPM. The OD seems to take forever to engage. It isn't really jerky when it does it, it just doesn't seem normal for it to shift up 3 times within 5MPH of each other.

What could cause such an issue?

Gr1m · 12-08-2008, 07:52 AM

that would be normal.....your tranny changes gears and the RPMs go down lol

K8TEK · 12-08-2008, 07:53 AM

Quote:

Originally Posted by Gr1m

that would be normal.....your tranny changes gears and the RPMs go down lol

It shouldn't change 3 times within 5 miles per hour.

Gr1m · 12-08-2008, 07:56 AM

if you ease up on the gas at 35 mph it will shift from 2nd to 3rd (RPMs going from 3k to 2.5k) and then shift from 3rd to 4th (RPMs going from 2.5k to 2k) and by the time your at 40 mph it would have shifted into 4th gear and be at 2k RPMs

Nate's Alero · 12-08-2008, 08:55 AM

makes sense to me, mine is the same way.....floor it and see if it downshifts, if you are worried,

have the tranny flushed...

Redog · 12-08-2008, 10:33 AM

Doesn't sound like a problem to me

lonnie · 12-08-2008, 10:37 AM

Sometimes if there is a problem a tranny flush can worsen it. I'm scared to get mine done cause I haven't changed my fluid since I've had the car for the last three years...LOL. I added the Lucas oil trans extender to mine and it is smooth as a babies ass. LOL!

cherrington17 · 12-08-2008, 11:12 AM

as the car ages/gets more miles... (or depending on how beaten it was before you got it) the trans will start to shift harder. its a machine, its going to wear some, and when it does... your gonna notice it.

the more gradual you raise your mph, the softer the trans is going to shift. mine really jerks when i'm flooring it... but if i'm just granny coasting in traffic, it don't even notice.

K8TEK · 06-22-2009, 06:19 PM

Ok, since this is my thread I am going to bump it up. The car is bucking when it is shifting. When shifting into 3rd gear, it is very sluggish and when shifting into second gear, it is rough. The transmission fluid is clean.

The car has 101,000 miles on it. I replaced the IAT sensor and the IAT sensor pigtail, cleared the computer and let it relearn. The OBD isn't giving me any codes, could this be a TPS issue, a shift solenoid or a TCC solenoid?

The TPS makes sense since the rpms fluctuate so much.

zzyzzx · 06-23-2009, 09:56 AM

Quote:

Originally Posted by lonnie

Sometimes if there is a problem a tranny flush can worsen it. I'm scared to get mine done cause I haven't changed my fluid since I've had the car for the last three years...LOL. I added the Lucas oil trans extender to mine and it is smooth as a babies ass. LOL!

At 100K, you should be OK with dropping the pan and replacing the filter and then refilling. It's when you do a flush on a car that old or (usually much older) is when yuo get the problems. I'd recommend changing the filter and whatever flud comes out when you take off the pan, but when you refill use the high mileage formulation of the transmission fluid if you can get it.

jackal2000 · 06-23-2009, 10:17 AM

on the other hand, it could be something mechanical inside the tranny in which case, flushing the fluid and clearing the PCM, etc will not help. only option would be to have it torn into by a tranny guru for an assessment.

CactusWill · 06-23-2009, 10:30 AM

Is the fluid the correct level, you do know how to check it right?

K8TEK · 06-23-2009, 12:29 PM

Quote:

Originally Posted by CactusWill

Is the fluid the correct level, you do know how to check it right?

Not exactly.

leoalero · 06-23-2009, 01:34 PM

on a flat floor,engine running while checking!

zzyzzx · 06-23-2009, 02:27 PM

I would seriously consider Seafom for the transmission.

K8TEK · 07-08-2009, 05:04 PM

Well, the shop said it was the TPS, which it wasn't. I let them replace it, and after I checked their work, I noticed the vacuum line going to the MAP sensor was dry rotted badly. I replaced the vacuum line and all is well.

zzyzzx · 07-09-2009, 11:11 AM

Quote:

Originally Posted by lonnie

Sometimes if there is a problem a tranny flush can worsen it. I'm scared to get mine done cause I haven't changed my fluid since I've had the car for the last three years...LOL. I added the Lucas oil trans extender to mine and it is smooth as a babies ass. LOL!

At 180,000 miles I just did the fluid anf filter change on my 1995 Escort. Still even had some of the original fluid in it. Got out a total of 4 quarts of transmission fluid vs my usual 2.5-3 via a siphon. Well worth the effort too. No negative effects after driving the car for 4 days in Baltimore-Washington DC traffic. If you are scared you can just change the filter and put the crappy old fluid back in.

JLw7123 · 07-09-2009, 11:14 AM

my speed sensor went and that messed up the rpms and the tranny did not shift smoothly have you checked that