Issues with 1995 GST Auto Transmission?

[LxiMax]

I'm not sure, but this could be an issue or nothing at all. I'm still getting used to how this Auto works. My issues are these:

When going into Drive, I start to pull out and I no longer hit maybe 1500 rpms and the car shifts into Second. Then, going from Second to Third, I have a slight flare in the RPMS, maybe about 200 rpms or so. Then the car will continue into OD sometime after 40MPH.

Next, when going down a hill, regardless if the OD is on, the car will downshift and rev upwards of 3-4k in what I'm guessing is an attempt to slow the car down. It will stay in this behavior until re-applying the gas or coming to a stop.


Is this just normal or could there be another underlying cause?

 

[clipto]

Yep thats a auto for you mine does the same thing. From what im gathering if I am understanding what your saying just check the fluids make sure thats good and make sure the trans gasket is good. How many miles on your car?

 

[LxiMax]

Just rolled over 83k. I know for a fact the previous owner more then likely has used the WRONG tranny fluid for the life of the car. Every time it needed done, he'd take it to Firestone and have a flush and fill done. The fluid was clear too, never seen clear fluid but I know most places like Firestone, Sears, etc. use a universal Dexron which is a severe no-no... So I instantly changed the pan fluid and filter to ATF+4. I'm probably going to change it every 1,000 miles or so until all the clear fluid is gone or take some time and follow a guide on here to flush the car by taking the two lines off the transmission going to the radiator.

 

[clipto]

I personally used napa atf, but you get it checked out if you want. I wouldn't flush it like that so often personally, also that would be alot of money spent I know there is a guy on this forum named blazinglaser_90 he lives by you, maybe he can help out shoot him a pm. Auto tranny's can be stuborn so check it out and find good fluid dsmers trust for auto trans.

 

[LxiMax]

This may also be me overanalyzing but I think I may be missing a gear? I'll start from a dead stop, light acceleration. First shift at 10mph, second around 20mph, then the fluttering third around 30 mph, then no more shifts, like OD doesn't kick in. It's around 2500 rpm at 55 mph. And on the flipside, w/ OD off, it shifts at 10mph, then 20 mph, then no other shift. Odd?

 

[LxiMax]

So from reading across four forums it seems this issue is fixed by a new End Clutch kit from Alto or IPT.

 

[rEclipserGST]

So from reading across four forums it seems this issue is fixed by a new End Clutch kit from Alto or IPT.

I had an issue with having NO 4th gear. 4th gear = OverDrive. I replaced the end clutches with the IPT kit, fixed. My car was scary to drive on the highway with the rpms that high constantly.

It is easy to install as well & you do not need to drain all the tranny fluid. Only replenish what you lost, but it is always good to replace the fluid.

 

[LxiMax]

So I reset the computer today and it's shifting without flares but still no OD. And it kinda slams down into gear coming to a stop. Glad I ordered the IPT kit.

 

[clipto]

The kit may be your answer if your trans is acting up. Has it always done this?Also depends on your throttle positions during the shift if your on and off the gas or at a low throttle it will shift at different points and usauall during 2nd or 3rd gear it will kind just rpms becuase the auto is trying to guess what shift points to do based on how much throttle your giving it while driving.

 

[LxiMax]

In the short time I've owned it, yes. The TPS controls how it shifts?

 

[clipto]

No but at different throttle points and I mean how much weight you put on the gas pedal the transmission ecu(tcu) and engine ecu will determine when to shift. If your cruising slow your engine will shift at low rpms and can be a little jumpy if your bouncy with shifting depends on how you control the gas pedal.

 

[LxiMax]

Ah that explains a lot. I was always wondering why it shifts at such low RPM's. I don't have a heavy foot unless passing someone. Still no OD though. I've gotten it to go into OD once, I was driving w/ damn near no throttle down a long straight road and it went into OD. Hasn't since. Rests at about 2500rpm on the highway at 55mph, which is odd considering there is no OD.

 

[clipto]

what rpm is it at when your at 60mph? Should be around 3000rpm with fwd you ganna have high rmps should be about 3 grand rpms right?

 

[LxiMax]

Ill check next time I take a drive. I want to say about 2800rpm at 60. But it doesn't feel like OD is engaged. I could be wrong though, I just don't feel a shift after 35.

EDIT: At 60mph, I'm at roughly 2600-2700rpm.