Hey guys!

So I had a male friend of mine take 06 MC 3.5l to get the transmission fluid drained a few days ago and since then the car has just not been driving the same. Digging deeper into to this fluid drain I found out that the wrong fluid was put it. They used Dex/Merc fluid and now I'm freaking out. I want to get this taken care of ASAP so I need to know if I need to do a full tranny flush? My car ask has 120k on it. I'm kind of scared to do the flush because I heard it can destroy trannys. Please give me some guidance guys.

Thanks,
LaVera

 

When your male friend took it in, was it flushed or pan dropped? The way the fluid was changed may explain the behavior. I thought most GMs used Dex fluid (I looked up an '05 Monte and found it uses DEXRON-III trans fluid).

1. - Don't have the fluid flushed. Most people who experience trans problems experience it after a trans fluid flush. Always pan drop and filter change.
2. - If the shop used the wrong fluid (per your owner's manual), hold them responsible. Make them change the fluid via pan drop. Using the pan drop method, to clean all fluid out of the trans, it's typically recommended to perform 2-3 pan drops (roughly a week apart). If you hold the shop responsible and a more permanent problem is generated by use of wrong fluid put in by their mechanics, they could be responsible for premature failure of the trans (or I would hold them to it).

Make sure to verify that they truly used the wrong fluid first.

 

I had the pan dropped. That sounds like a good idea.

Thanks

 

How often should the pan drop be done?

 

Changing trans fluid intervals depends on some variables:
- Climate
- Do you drive up and down steep hills
- Your average driving (freeway vs stop-n-go city)

The owner's manual goes into detail about the condition and change intervals. For me, I do at before or at 100,000 miles (that is in northern Ohio).

Also, any time you change trans fluid.... ALWAYS pan drop.

 

Thanks I'll be sure to keep that in mind, I rarely drive my car so its got a ways to go to get to 100k and its Iowa, a few hills but pretty flat. Plus most of the time i tak ethe car for a cruise or two or maybe around town a couple of times thats aobut it.