Check the transmission fluid with the engine warmed up and running, with the car parked on a level surface. Otherwise it's always going to read high, as the trans fluid drains back into the pan after the car is turned off.

 

Also if it is dirty you can do a pan drop, change the filter and refill what came out. I don't recommend a full flush.

 

ok i may consider doing that.it wont be that my cat is clogged?

what are the pros and cons of completely removing the cat?

and same question for the resonator.how will it sound?

 

Resonator will add drone to your interior, not fun.

Removing the CAT is illegal in most states, ESPECIALLY California, you will NEVER pass emissions lol

 

Dirty transfluid is not a good sign. How many miles are on the car? I'm guessing the transfluid and filter have never been changed... If that's the case, you are probably due or over due....

 

There are 130,000 on the tranny, most are highway miles.the engine was rebuilt like 4,000 miles ago.I'm not sure if the car has ever had The tranny fluid changed or the filter. I will be looking into that tho.

I ended up deleting the cat, but don't worry, I will be putting a high flow cat along with the u Bend delete in about 2 months.I'm not due for a smog for about 1 3/4 years so it's not the biggest rush, tho I don't want to hurt the earth more than I already am.lol
The magnaflow cat on zzp fits our Montes with no problem right?

 

ZZP Downpipe fits without any issues, but will most likely throw a P0420 code and you will still fail emissions (unless you get a ZZP PCM also and have the code deleted so it never shows)

 

RandomTech makes a SS Hi-performance down-pipe and cat in 2 versions (2.5" & 3") that will fit our cars. Look under Impala (same year) if you don't see a Monte Carlo listing. I have been using the SAME Random Tech 2.5" down-pipe without ANY trouble codes since 2006. I like ZZP, but most people throw trouble codes with their cats and it's not worth the hassel.