I have a problem sometime the van will up shift hard. The fluid and filter is new(less than 10,000 from last change) Fluid level is correct. The odd thing is that if you let the van sit when the problem starts it goes away. I don’t think its a heat problem I just drove it out of state 2 1/2" hours each way no problem? Any thoughts. The van has 118,000 miles. Thanks
A question: what was the mileage/length of time between the last fluid/filter change and the one before? Approximately 108k miles at the last change?
Reason I ask is due to your statement of “if you let the van sit when the problem starts it goes away”.
This suggests to me that any dirt/metal shavings (foreign material) drops from filter to bottom of pan leaving a clean (or partially clean) filter to keep things running until the filter picks up the foreign material again.
I have a 2000 Silhouette that started a ‘harsh’ shift too, but fortunately for me it was cured by a close extra fluid/filter change.
One problem (I guess among others) I read about is the pressure control solenoid in this tranny can become damaged and quit, causing harsh shifting.
I have no idea what this solenoid would cost or the cost involved changing it.
Transman18 is our resident tranny expert, he’ll have more knowledgeable input for you.
how long time and mileage has this been happening?
by any chace have you disconnected the battery lately?
when you disconnect the battery is erases the memory the car computer builds up about transnission shifting and efficiency. it takes a whiel to “relearn” the memory.
Well, dont go trying to clear any codes just yet. You need to scan the computer and see if it has set any codes. Take it to a local auto parts store who scans computers and see what codes if any have set. Post back with the code/s and we will go from there.
The filud was changed at 52,000 when I got the van and about three months ago. This started about 2,000 miles ago. The first time it happen the van sat over night and it did not do it for about a month, now it hapens once a week now. I have parked the van unitll I get my free money this spring from MR.Bush(I know nothing is free) so not to do any other damage to the trans if that is the problem?I have no trouble codes stored or active. The pressure control solenoid from what I know you almost have to remove the trans to get to the cover off to get to it. If you have to go to all that trouble to do this should I think about having an overhall with it having over 100,000 miles on it? From what I have read and know GM trans have major problems after 100,000. I had two chevy trucks an 88 and a 96( 88 is my falt I put a lift on it late in the trucks life) had to rebuid the trans at about 120,000 . I have to keep the van untill spring of 09(still paying the bank)
I wouldnt go throwing parts at it. I would let a transmission shop scan it. The pressure control solenoid can be checked and tested by using a special scanner. A trans shop will be equipped with the proper scanner to test the solenoid. That transmission can be tested both electronically and hydraulically without removal of the transmission or transmission pans.