I got a flowmaster put on my ranger and now my transmission won't stay in gear it 1-3-5 but 2-4-R are just fine. I had a straight pipe on it before. If i stay on the gas it will stay in gear but if i let off it slip out of gear or going down hill the same. it will shift just fine before i got the muffler put on.

I have a 4.0 5-speed manuel

STC XCAILBRATOR II

K&N COLD AIR INTAKE

 

Bump

 

Only possible way I can see it hurting your tranny is if you accidentally messed up your linkages or pulled out a wire or something.

 

Ok so get under your truck and visually inspect everything. Did you go cat back? Or was it just muffler on off? It could be ironic to have the problem right after, just a fluke

 

or when you had the muffler installed, they didnt pull the neg side of the cable when they started welding the exhaust, could have screwed with your computer system..... IMO

 

Wow I have NEVER disconnected the battery to weld exhaust, nor have Ive seen that done, in my opinion that would cause NO problem what so ever.

 

No battery was not disconnected when the muffler was installed.

i have the whole system on. cats and muffler

 

gotta be a fluke....espicially since you have a manual. Mayeb it's time for that crappy mazda trans to be replaced. My '01 is acting up on me too.