Occasional transmission slip from complete stop

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

clandr1

Full Access Member
Joined
Apr 20, 2012
Posts
910
Reaction score
999
Location
Dallas/Fort Worth, Texas
Hi everyone,
I've been dealing with this issue for about the last 30,000 miles or so. It started after a fluid and filter change around 195,000 miles.

On occasion, the transmission will hesitate/slip when I begin to apply gas to start moving after coming to a complete stop at an intersection. It typically only happens at stop signs where there is a brief stop/start. When I sit at a red light, it typically is not an issue.

I wonder if there's a problem where my transmission isn't fully downshifting into 1st gear as I'm slowing down? Outside of this specific issue, the transmission shifts beautifully and works well, and is original (not rebuilt). I've taken care of it and with the exception of a dealer flush at ~30,000 miles, I've only ever done filter and fluid changes in my garage.

I should also add that on occasion it seems like when I floor the gas pedal on the highway, it takes a little longer than it should for the transmission to downshift. It's almost like the motor and transmission don't know I've floored it for about 2 seconds.

Is there a solenoid that could be going bad and in need of replacement? I've seen reference that a bad throttle position sensor could cause some of this, but given this issue started around the time I changed the transmission fluid and filter, I'm inclined to think it is not the TPS.

Thanks in advance for any input or suggestions.
 

Mudsport96

Full Access Member
Joined
Jun 6, 2020
Posts
1,167
Reaction score
1,781
Location
40.923,-89.488. Illinois
Everything you describe makes me think tps. But, there is always the possibility it is trans related. What year is the rig? Drive by wire or cable?
 
OP
OP
clandr1

clandr1

Full Access Member
Joined
Apr 20, 2012
Posts
910
Reaction score
999
Location
Dallas/Fort Worth, Texas
Everything you describe makes me think tps. But, there is always the possibility it is trans related. What year is the rig? Drive by wire or cable?
Sorry, I thought my rig info was in my signature. It is a 2005 SLT 5.3L Flex Fuel. Based on a YouTube video I just watched, I believe my TPS is drive by wire.
 

afpj

Full Access Member
Joined
Sep 16, 2009
Posts
780
Reaction score
311
you likely checked already, but fluid level good? Consider changing the fluid, again. While you have the pan off, check the filter, check the magnets. Main reason is if this started after your last fluid change, recheck whatever was done right before symptoms started. Just saying. What fluid did you use?

Btw, I don't think there's a weekend crew. This forum typically has much less traffic on the weekends.
 
OP
OP
clandr1

clandr1

Full Access Member
Joined
Apr 20, 2012
Posts
910
Reaction score
999
Location
Dallas/Fort Worth, Texas
Yes, fluid level is good, I've changed the fluid and filter twice since then, and nothing out of the ordinary was in the pan or on the magnet. I used Delco transmission fluid that matched the spec for the transmission, and a Delco filter/gasket kit. I'm completely at a loss for what happened. Maybe the transmission was old enough that it just didn't like the new fluid for some reason?
 

Forum statistics

Threads
129,125
Posts
1,810,832
Members
92,211
Latest member
patrickleeleep
Top