So I just had a new Tru-Cool LPD 4588 transmission coller installed (as well as a new muffler at the same time, just in case that could be relevant).

But ever since, the 4Runner just seems slower than it used to be. Sluggish.
Shifting seems fine, but the acceleration is definitely lacking.

Can cooler/cold transmission fluid cause the thing to lose power?
It is cold here, is it the external cooler coupled w/ cold weather?

Any ideas?

 

I think you need to ride like your avatar less and you're imagining things.

:wabbit2:

 

No, it's a noticable change. My wife pointed it out to me. Drove it and couldnt deny it.
It is definitely slower.

 

Any exhaust leaks from the muffler? What sorta muffler?

 

I had a shop (owned by a friend) put them both on. It's winter and my garage floor is cold.
I am not aware of any leaks. The muff is a who knows what brand aftermarket replacement, but it is definitely louder than stock. Sounds more like it was meant to be a performance muffler than stock replacement.

 

OEM muffler replacement, or one from the likes of George Foreman (Meineke)?

And no, the tranny would not cause such. Good cooler to use....

 

Not OEM. A buddy of mine owns a small auto repair shop. They got it from a local Exhaust warehouse. That's all I know.

 

wrap your cooler in cardboard and run it (not all day, but enough). does hotter tranny fluid change the sluggishness ?

 

Why did you replace the muffler in the first place?

I had a friend replace a muffler on his Ram due to a hole in it, he replaced it and the truck did not quite run as well. Turned out that his converter had been on its last leg and did not mate well with the new Magnaflow. A new cat and all the power was back. You may want to take a look at the converter.

I have run ATF at 105~110 degrees all day before in the winter. Not good for the tranny but there were no ill effects as far as I know.

 

check the receipt from your friend's shop, it should tell you what kind of muffler.

check to make sure they properly installed your cooler w/o any kinks etc...

 

Is it possible they installed the muffler backwards?? I know flowmasters are directional but I've never worked with any other aftermarket ones.