mclark100

I have a brand new 2010 Silverado 4WD with a 5.3L/6 speed.

I love it, but it always feels like it's in a gear lower than it should be. I notice it especially at slow speeds, less than 40. If I take my foot of the gas, it feels like the engine is braking, instead of coasting.

So if I step on the gas again, it's a hard start - not a smooth transition, kind of like driving a manual tranny in the wrong gear.

In stop and go traffic, which changes constantly, it's a pain.

I mentioned it to my salesman and he said it's a characteristic of the engine and 6-speed tranny combo.

Any one else see this? I suppose I could ask to drive another one with the same setup.

s34n

what you could do is find a shop in your area that can reprogram your transmission shift points. they could make the gear shifting smoother or more firm. pending on your preference.

nauticstar87

Sean is right. With my 6.0 with 4.10s with the 6-speed auto, I feel that it jerks at times it shouldn't. But I beleive it's the nature of the beast. I think the 6-speed just needs some tuning. After my tune, I was much happier with the shift points.

mclark100

Thanks for the info guys.

But I'm not so much concerned about how it's shifting or the shift points (which seems fine when accelerating), but more about the actual gear it's in when slowing down.

Mileage seems okay at 17mpg, and they're not highway miles.

When I let off the gas, it slows down quicker than I expect, almost like it's braking, and I don't feel it downshifting. I even double checked to make sure the e-brake wasnt partially engaged. If I let off the gas approaching a light at 20-30 mph, it almost stops itself after 50-60 feet.

Of course, it could just be my imagination. I'm just not sure what to check because it doesnt seem right.

But then again, maybe tweaking the shift points of the lower gears would help...

tsduke

I don't have a truck 6 speed, but my wifes 2011 Equinox is a 6 speed. So is my fathers Camry and I thinks it's just the nature of the 6 speed design. Coasting just isn't there, like you say with foot off the gas it acts more like an engine break.

Since I don't drive her car a lot it's certainly very noticable versus driving my 05 Silverado 4 speed.

mclark100

Thanks!

It will be interesting to see if others report the same "coasting" thing.

My old truck was an 87 Silverado with a 350/4 speed, and its sure different here, too.

2wd-K5

the new transmissions today all have lock-up torque converters, this is to provide a positive lock between the engine and trans so there is no power wasted on slippage
this tech has been around for over 30 years but now it is being programmed more agressively, this is why it seems like it is braking at a coast because it doesnt dissengage (it used to in 700r4's) this also is why it is harsh when re-applying the gas too. i would think the reason it doesnt dissengage is for milage and wear concerns, if it was always engaging and disengaging every time u let off the gas im sure it would cut the life of the trans down, go drive an old ford (sacrelige i know) their C4 trans does this and is very harsh (the fix i found for the harshness is putting a little grease on the slip yolk and the female spline at the transmission output shaft, and as for the lock up timing all together, a programmer will solve how it works, but at least now we al know why it is like this...just gm trying to save themselves unessesary warranty work and to save u money at the pump

mclark100

That makes sense. I just wanted to make sure it wasnt a problem. New technology - That's what I get for waiting 25 years to buy a new truck.

Thanks!