I have an 04 SS n/a with about 70,000 miles on it..... the car has been great to me all summer, zero problems..

but recently since its started getting real cold around here for the past month or so i noticed that the car will shift real hard into 3rd gear...

For some reason i noticed the car is usually fine if its just me, sometimes it slips when im alone...but as soon i pick someone up and they get in it starts to shift funny again as if the added weight is a problem or somethin

Any experience or advice with this would be greatly appreciated

 

Cheap test... A shop can hook up a port to test pre-catalytic convertor pressure. GM's have problems with the cats going bad, which can cause trans to act up. If it comes back normal levels then you know it wasn't the cat. Just don't take it to a exhaust only shop... they're prolly going to tell you what you want to hear just so they can make a sale.

The plugged cat should be covered by warranty if ur still under 80k. They extended the warranty on them.

For some reason the trans thinks it is slipping, so it increases the line pressure, resulting in the hard shifts.

 

my cousin said it was probably the cat too... ima get it checked out soon.. thanks for the advice

 

i got a 03 ss, and mines used to have that problem. from time to time it will come, and go. i have a heavy duty tranny cooler too, now till this day it havent did the hard shift, or slipped, honestly, i just drained about a 1/4 to 3/8th of tranny fluid out, and its been very smooth ever since, this was in july also. im not saying do what i did, just make sure you dont got to much fluid in there.

 

hows your tranny stl_chevy-rider??????

 

well since the weather here has been in the mid 60's to 70's lately it hasnt been doing it much but im still going to get it checked out next friday when i get paid

 

sucks, i hope it wont cost to much, or even better i hope its not a big problem

 

hey i'm having that same problem right now. My 78" does not shift to third gear and when it does it's a real hard shift. So if you ever find out the problem make sure you update us cause i might try the same thing.

 

Let us know how that goes. You might also want to have the transmission oil and filter changed, but my bets are on the cat as well.

 

I dunno, a 78 wouldn't have the same trans, being RWD, so I doubt a clogged cat would effect that trans as much.