Poor/Sluggish Shifting Following Gibson Exhaust, Sliders and Bigger Tires (1 Viewer)

[mstrsltr]

I went from stock 2008 GX470 to the following:

1.) Metaltech OPOR bolt on sliders (150lbs?)
2.) Falken Wildpeak AT3 265/70/17 (weight vs stock duelers?)
3.) Gibson Catback exhaust (N/A)

The shifting has since gotten weird. It’s poorly timed, sluggish and all around crappy.

I drove the truck for 18 months before adding any of the aforementioned mods. It always shifted beautifully, and more importantly, powerfully when needed.

I know adding weight to anything in life will slow it down. But these tires aren’t THAT much heavier, are they? They are taller, but tall enough to mess with gearing? The sliders are probably the same weight as a healthy adult male. All of it combined can’t weight more than 250lbs.

But the truck doesn’t feel slower due to weight, it feels slower due to crappy shifting.

Could it be that it’s actually the aftermarket muffler thats responsible? Because typically they’re supposed to improve shiftIng.

Or is it all of the above?

It’s not that outrageous as far as mods go, but I’m surprised I haven’t heard similar complaints from others who’ve done similarly modest mods.

 

[joabmc]

Disconnect the battery for awhile, let the computer reset in order to relearn your new driving habits.

 

[Jstawgn]

Did you reset the ECU? Some of the learned parameter would need to be reset to speed up the learning process.

 

[mstrsltr]

Didn’t realize that was required.

Can I reset ECU by disconnecting battery?

Thanks!

 

[Jstawgn]

Yes. Just disconnect for more than 30 sec. You would need to reset window auto up down, radio and memory seat after that. Might be sunroof too but mine does not want to that after opening fully open and close.