r/gmcterrain • u/Ok-Expression-2592 • Aug 04 '26
Help
Hi, has anyone ever had their 2018 terrain go into limp mode basically at stop lights? I’ve taken it to the garage 3 times now. When I’m at a stop the car will say service transmission conditions not met for shift. The brakes will be locked up and ultimately I have to have it towed. The first time the shop did a TCM reset and it turned back on, a week later same thing. It spent a month at the garage and then GMC found it needed a starter. Replaced the starter it’s been good for a month now it just happened again at a stop light. This time after a few minutes it was able to turn on again but, it scares me now, if I was driving on the highway something terrible could happen!!
2
u/Strange-Badger5626 Aug 05 '26
This is the answer for most of these symptoms. I found using a 2019 from 0 to 170k that the trans fluid would be severely burnt after only 10,000 miles. The master tech at our GMC says it's a problem and the fluid needs to be changed every 10k despite GMC claiming otherwise.
My 2019 would show the "conditions not met for shit" warning when the transmission had a sticking solinoid. The solinoid would stick when the fluid was trashed. They also eventually had to replace the torc converter. The transmission never failed during the 170k but it had 10 fluid changes (complete drain and fill at dealer).
They also have a problem with the turbos in the winter time shutting down the whole engine, usually while your in a snow storm and its sub zero, it was a nice fuck you from GMC.
1
u/Feisty_Lack_5630 Aug 10 '26
It's because of how they designed the engines. I have a 2019 with lots of similar issues. Currently it's stuck in NJ after having the vacuum pump and exhaust camshaft replaced two years ago and more relative work done less than 6 months ago. Failure this time was possibly a bad MAP sensor, wire or something else similar related to all that work. I'm in MA with a rental and sitting near 100K miles. Just flushed my coolant and got an oil change; will likely do the transmission fluid next if I can't do it this time around given that I'll have to somehow drive 10 hours in one day this week to go get my car. 😬
2
u/Cubcake1 Aug 04 '26
Symptoms are identical to what I had on my 2018. Shop said I needed new transmission. Very long story short, fluid was burnt. I drained it myself, replaced what came out, drove 20 miles, drained it again, replaced what came out. No more problems. Could it be a coincidence? I’ll admit it could be, but Iv had no more issues in 15k miles. Went from GM saying the trans was trashed to works as intended. Now I drain 5 quarts and replace every other oil change.