Auto Transmission slowing truck down

Have a BRAND NEW Tacoma 2wd AUto Trans w TRD Off road w Towing package.
OK, I have had the Truck exactly ONE week. I have had several 4runners and have a 4runner now. This truck has me puzzled a little.
When driving along at say 50 MPH and getting near a Turn or Stop,(I drive Light footed!) I let off the gas and want to sort of coast to the turn or stop light, especially if going slightly downhill, and the truck really starts to slow down much quicker than I am used to in the 4runner. IT doesnt seem to coast along, it seems to be downshifting and going into a lower gear or something and while it does have the feel of total control, it has got to be hurting the MPG's.
The 4runner will coast when you take your foot off the gas pedal, the Tacoma seems to want to downshift.
Is this simply a matter of the Truck being geared so differently it is setup more for Control and Towing? Seems the rear end is in constant control, no coasting at all.
I am having to give it the gas going downhill toward an upcoming turn, which in the 4runner the vehicle would be gaining speed going downhill toward the same turn. Both have AUTO Trans. Both are 4.0 V6 and both are 2WD.
The Tacoma is NEW with TRD Off Road package and Towing package.

Just got my first fillup after 300 miles and my MPG is 17.1. The 4runner I have always gotten 20 to 22 MPG with the 6 Cyl, and it has more weight.

I have read and searched and don't see a whole lot of discussion on this.

Forgive me being such a Non-Mechanic with my description!!!

 

As for the mileage, give it some time and it should work itself out. Let it break in and you'll be ok there.

 

Don't know about that... As for the downshifting, the new tacomas are designed to help you brake so thats why it will slow down quicker. It's not designed for MPG's for that you want a Prius.

EDIT: You'r MPG is better than my 14, I'd say 17 is about avarage and wont get much better unless you change your driving habits.

 

Believe it or not... I traded a PRIUS to get a Tacoma!!! I used the Prius to Commute for 3 years and put 93000 miles on it. Due to Transfer I only have to drive 3 miles to the office now so I wanted a Truck!
I know how to drive to get the best MPG's from driving the Prius... Basically light on the gas pedal and ease to your stops.

I started this thread to hopefully get some insight to why the Tacoma feels like its downshifting into a lower gear while coasting downhill to a stoplight. The 4runner I have coasts down hill more and gets better MPG. I guess it doesn't make sense to me!

 

That's all normal.... give it time to break-in.

What tire pressure are you running? The doorjam (atleast on mine) says to run 29psi. Personally? I think that's too low. I've bumped mine up to about 32-34psi. That might give a slight edge on the gas mileage.

Nice Truck!!

 

the tacomas are made to slow down as soon as you let off the gas petal. everything is normal. as for me i like it, never driven anything that does it.

 

normal, and normal. Go easy on the gas and you'll get better MPG. Just needs to break in.

 

^I concur. Mine easily went up 2mpg over the first 10K.

 

The Tacoma's and other new vehicles have a trick in that when you are coasting the ECU will shut off the injectors, so, yes, the revs are up, but fuel consumption is 0.

 

My wife's 09 Camry does the same thing. She likes it, especially when going down mountains.

 

Mine being the 6 Spd manual it is different then what you are talking about but this is what I found about coasting under compression and fuel consumption.

We have a highway with a rolling downhill grade here that runs between 1 an 5%, the other day I was coming down under compression doing about 50 mph and the scangauge real time showed I was getting between 46 and 64 MPG, I popped it out of gear and the scangauge immediately went between 69 and 84 MPG depending on how fast I was coasting.

Out of gear my truck will never go below 1200 on the tach unless I am under 10 MPH


So what I found it is using more fuel under compression then when rolling along out of gear

 

Nah, I think Chris is right-- The injectors shut off for engine braking. This means your not putting fuel in the engine. At idle, in neutral you are still injecting fuel into the engine. (I think).

 

I always wondered about this too. My old Ranger would coast forever. Thanks for clearing it up.

 

I have a 06 TRD double cab 4.0L and never get over 20mpg. (38000K on motor). If I coast it for 18 gal then I can milk 400 miles on 18 gal. But driving under 2K revs takes a lot a patience and time. I have noticed that if I am light on the pedal and coasting down hill sometimes it will hold a lower gear until I hit the gas.(like a jake brake on a 18 wheeler)

 

In my 06 I've noticed that while coasting if I just barely apply a little pressure on the gas pedal, and I mean "very light pressure," It will act as if its coasting in neutral w/o the braking effect.

 

Yer kiddin, right?

 

My 6 cyc, 4X4, automatic, TRD Sport truck now has 17K miles now. Until yesterday, the automatic trans did not downshift on its own.

- For the first time yesterday, I was coasting down a hill.
- The trans was in "D". I felt the truck downshift.
- I looked at RPMs. They went from 1100 to over 2200.
- While still coasting down hill, I manually shifted into "4". The RPMs did not change. I immediately shifted back into "D" and the RPM jumped from over 2200 to 1100.
- The truck clearly downshifted on its own although the dash shift status does not indicate the trans has shifted from "D" to "4" (unless I shift it manually).
- Same thing happened this morning.

What appears to be happening is the trans is being shifted from its overdrive to 4th. What I don't know is if engine braking is an "undocumented Tacoma feature", or a problem. I can't find anything in the owners manual. I know if I call the dealer I'm going to get the patented "they all do it" response. Anybody know for sure?