sneakyslide

I am looking to purchase a 2004 4-Runner. I have driven it, and as you go to stop, you can hear a whining noise, it almost sounds like someone is putting down a power antenna. I believe it may be something to do with the ABS braking system and the down hill assist control, even though the down hill is off. The dealer tells me its just the two working together even though its off. Any other ideas or suggestions regarding this? Has anyone even heard of this before?

Any feedback would be greatly appreciated.

Thanks.

xthirdimpact

Hi Sneaky. Welcome to the Forum!

I have a 2003 4Runner Sport Edition V8 and mine does something similar to what youre describing.

Everyday on my way home from the gym i have to go down a long, semi-steep hill....the moment i reach the crest of the hill and take my foot off the gas, i let the vehicle coast a bit, then touch the brake...and i feel the vehicle's systems engage as if it were "downshifting" to put less work on the brakes. Afterall, this vehicle is 5700 lbs. and doesnt exactly stop quickly.

I called my local toyota tech people, as well as a very well-trusted (if there is such thing) dealer that has sold my family many toyotas, and he looked into it with this lead techs. Turns out that even without the "downhill assist" there is a component that engages a down-shift to help stop the vehicle.

All i will add to this is the importance of the scheduled maintenence. I think at 15k or 20k or so there's a "change fluids in differentials" and the tranny, and i would always tell an owner NOT to ignore that.

Good luck with the '04!

ysr_squid

The booster on the 4Runner is electric rather than vaccuum off of the engine. The whining that you hear is the motor building up vaccuum consumed by the brakes as you come to a stop.

BTW - I have a 04 4Runner and it is an AWESOME truck.