So I have a 2006 5AT. Passing a truck yesterday, hammer time. Down shifts from 5th to like 3rd, great. As she rounds out third gear, I hear and feel a loud POP, probably during the shift. I let off immediately and exit the fwy. Tail between legs.

No CEL, shifting seems normal at this time, no other signs of trouble.

Should I be worried?

 

You may want to flush your tranny with this stuff:

GM Synchromesh with 5% Friction Modifier = GM 12377916

Threads to read:

https://acurazine.com/forums/showthr...highlight=gear

https://acurazine.com/forums/showthr...highlight=gear

https://acurazine.com/forums/showthr...highlight=gear

 

Thanks! Does this apply to my automatic transmission as well though?

 

No! He didn't see that you're an AT. Do a search. Lots of discussion on which AT fluid to use, 3x3 flush procedure, and replacing 3rd and 4th pressure switches.

 

Yeah I did the switches a few months ago, redline fluid is forthcoming. It just seems a transmission should never pop/scrape like that though.

 

The pop could have been a backfire from crud that broke loose off in the exhaust. My MDX had this happen a few times when it was new.

 

Probably an intake backfire. Mine has done it maybe once a year since I bought it brand new. It seems to be when I'm barely backing out of the throttle from full throttle and it upshifts. In my case, it's for sure an intake backfire. This is usually caused by a lean condition but in this case it seems like it's rare and causes no problems.

Did it sound like it was coming from the front driver's side of the car?

If you have an intake it will be MUCH louder. With the stock airbox it's still noticeable but not the scare the crap out of you noticeable like with a CAI.

Glad to hear you're doing the Redline. Make sure to get the "racing" fluid or the "lightweight racing" fluid.

 

Exactly! It happened at basically the same instant I thought to back off the throttle. Driver's side, definitely, and no, no intake.

And csmeance, this sounds plausible too. It was easily a breaking-off sound.

Well cool guys. Seems I was unnecessarily suspicious of the transmission. But the brief scare really made that redline ATF a priority!

 

Sounds like that was it. It's not really necessary but you can always check the air filter to make sure it was not damaged. They will withstand a pretty good backfire so I'm sure it's fine but it's easy to check.