issues with new 2011 SR5 V6 4x4

[chromefinder]

The hiss/squeak/vibration is from the vacuum diaphragm and stuff that adds the power assist to the brakes. Most larger vehicles make a sound of this type because of this, with GM trucks and frame cars of pre-1995 doing this commonly too. Maybe they still do.

The transmission won't go to "near neutral" free rolling state right away on the T4R, which would allow the rpms to drop. What I find more annoying that once it does, about 2 seconds later, it takes its sweet time to re-engage when you lightly press the throttle. Some other transmissions are programmed this way, like the one on my 2001 Maxima, although it never really goes to a like near-neutral (and so the rpms never drop), and so it does not have the delay when you throttle back up.

What I find annoying is when you mash the throttle, and after a quarter second delay (thanks, "sudden acceleration" lawsuit parasites), the whole thing launches as if the jolly green giant had kicked it in the rear bumper. Something a little smoother would have been nice.

rpms not dropping when free rolling is one thing but my rpms actually jump up when free rolling, no foot on gas.- seems like the transmission is downshifting on its own. I can make it happen typically on long hills above 40 mph. With no foot on gas my 2011 SR5 V6 4x4 T4R free-rolls with rmps @ approx 1200 to 1500 then as i continue to coast the rpms jump to approx 3000 as they would on a downshift. This also happens on the flat. I just wish someone could explain to me why this is happening and if its design intent.

 

[Quentin]

rpms not dropping when free rolling is one thing but my rpms actually jump up when free rolling, no foot on gas.- seems like the transmission is downshifting on its own. I can make it happen typically on long hills above 40 mph. With no foot on gas my 2011 SR5 V6 4x4 T4R free-rolls with rmps @ approx 1200 to 1500 then as i continue to coast the rpms jump to approx 3000 as they would on a downshift. This also happens on the flat. I just wish someone could explain to me why this is happening and if its design intent.

That is absolutely intended. There is some amount of engine braking built into the transmission shift tuning so that you don't have to ride your brakes down a hill all the time. My mother's Yukon didn't do this and she had warped rotors every 20k miles.

 

[V8 AWD 4EVR]

I did not know about brake assist, but I think it kept me out of a rear-ender this morning on a wet, windy road!

V8

 

[chromefinder]

25K mile Update

25K mile update

my 2011 T4R still downshifts for no good reason too much - dealer has been useless.

I'd much rather replace a brake pad and the occasional rotor than a transmission.

I'm finally used to the brake sound.

 

[philsey]

25K mile update

my 2011 T4R still downshifts for no good reason too much - dealer has been useless.

I'd much rather replace a brake pad and the occasional rotor than a transmission.

I'm finally used to the brake sound.

The dealer cannot fix something that is inherent in the design.

Around town, I find the 5-4 downshift around 38-39 mph to be annoying. The answer is to drive in S-4.