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Discussion Starter · #1 ·
Engine - no comparison! I only have to put the pedal down half way to match flooring it in the 07. I can tell the difference in the DI. More power, quieter sound, and more responsive. MPG is not much better in the city for me. First 2 tanks were 13.5 (not much in the way of highway, all stop and go (lights)). Taking it on the road for a 1000 mile test this weekend, so I will see how it does on the highway.

Transmission - no comparison! I had the 2 flashes on my 07 last one being last May. Never would go into 6th on the highway unless I tricked it. Lots of shifting. Shifting is smooth in the 09. A side from the learning process (it learning, not me) the feel and response time is great. When I have had it on the high way it shifts smooth and stays in 6th like it is supposed to.

The overall feel and ride is much better. The bigger breaks (because I have the towing package this time) make a big difference in stopping as well. Smooth and soft, no gripping that I had before. No more squeeky pedal. No steefing noise.

This was a great decision to get out of the 07. The only thing I don't like, well actually 2, is no heated washer fluid - oh well, never worked well anyway, and the leather on the steering wheel and shifter feels synthetic and not like real leather. I think they saved money by going to a split grain that is tanned cheaper - although it is still leather.

Love the 09 - Love the Acadia! :thumb:
 

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I wasn't aware the 09 had bigger brakes with the tow package

I haven't been fortunate to drive on 09, but I would like to see the difference with the DI engine. I love my 07; the trans flashes have greatly improved the shifting and the ride and comfort are great. I put new Fortera's on this past weekend from Discount Tire (got the TPMS rebuild and then relearned everything without incident). Overall very satisfied, but as I said earlier I haven't driven the 09
 

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The brake size was news to me also. I don't recall reading anything about that, and can't check part numbers online since I don't see any listings for 2009 models yet.

The 2009 ordering info PDF (see Blues Clues) I have shows all models have "JL9" 4 wheel anti-lock disc brakes, it does not differentiate anything regarding the brakes for the towing package like it does for the cooling system.

The rotor diameters for both years is available online somewhere & this should prove or disprove the point.

It sounds like to me the pad material was changed from one to the other. Dodge did a similar thing in 2009 with the Challenger. They advertised "HD brakes" for the 20" wheel package on the manual shift cars. After a lot of research, we found it was just a different pad, everything else was the same.
 

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When I first read "HD brakes" I initially interpreted that as "high definition" brakes :crazy:.......next thought was "Blue must have mistyped that; how can a car have high definition brakes"?

Well I guess I'm the :crazy: one..........duh those are "heavy duty" brakes
 

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Discussion Starter · #5 ·
The brakes look bigger to me and a couple others have commented on them. I will be going to the dealer this week and I will make a better evaluation. In any case the Acadia brakes totaly different than my Outlook and the only difference is the towing package.

If anyone knows different, please let me know as looks can be deceiving.
 

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LOL sometimes we have to unplug to understand things. I'm sure HD (high def) has replaced heavy duty for many people in this electronic age of not only hi def video but high def audio as well.

Anyhow, I looked here:
http://www.autoguide.com/new-cars/2009/gmc/acadia/sle1/specs.html
2009 SLE:
Front Brake Rotor Diam x Thickness (in): 12.8 x 1.1
Rear Brake Rotor Diam x Thickness (in): 13.0 x 0.8

http://www.autoguide.com/new-cars/2009/gmc/acadia/slt1/specs.html
2009 SLT1:
Front Brake Rotor Diam x Thickness (in): 12.8 x 1.1
Rear Brake Rotor Diam x Thickness (in): 13.0 x 0.8

They didn't have listings for the 2007, so I looked here:
http://www.autoblog.com/2006/07/12/2007-gmc-acadia-revealed/
front: 12.8 x 1.1 / 325 x 29, ventilated
rear: 13 x 0.8 / 331 x 20, ventilated

Summary: All dimensions are the same, and I didn't see any mention of tow packages changing this.

When auto makers have offered two or more brake options on vehicles, this is usually due to a higher gross weight (GVW) rating (usually trucks- Sierra 1500 will have smaller brakes than Sierra 3500) or high performance models (i.e. larger motors). Again using the 2009 Challenger as an example the 6.1L V8 SRT8 model has larger rotors (14.2") than the R/T, and the 5.7L V8 R/T has larger rotors (13.6") than the 3.5L V6 SE (12.6"). The 2010 Camaro is similar (but has big brakes in all V8 trims :thumb:). It would be odd to me for GM to make two different sizes of front & rear rotors for the Lambda since there is no variation in the GVW and they all have the same motor.

Let us know what you measure on both.
 

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Discussion Starter · #7 ·
Well.... I bow to the numbers. :eek: But they still look bigger, maybe it's my glasses or :drunk:.
 

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if there were no strikes last year i might have waited for the 09. but then again, at that time they were offering very good discounts for the 08 that we eventually decided to pull the trigger. i am very happy with the '08.
 

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Not sure; IMO cooling isn't a big issue for this vehicle so it doesn't seem as though GM would look to replace the radiator already in use.
 

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The Friction Materials Standards Institute (a trade group that assigns part numbers to brake pads, shoes, blocks, segments, clutches) shows the same OE part number for all three years. While FMSI is not perfect (who is?), it is a pretty good source of info. The OE number would change if the pads were made of a different formulation, or had any other changes. I believe the pads are made by Akebono and are ceramic based material. Again, no one is perfect, so I will look into the pads question and report back.
 

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copperbeech said:
Is there any reason to believe that the towing package includes a larger radiator??
This was researched & discussed in another post, so I won't go into the details. The tow package calls for a different part # than the regular vehicle. I doubt anyone has taken them & done a side by side comparison on them like at least one person has done with the 2009 Challenger. :)

tm59,
Thanks for the research & info (now I know what that FMSI means :thumb:). It appears there is no difference in the brakes whatsoever other than possibly an upgrade in the OEM material.
 

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I guess they have different part numbers so they must be different radiators; you are supposed to have increased cooling with the tow package.
 

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jsimms said:
I guess they have different part numbers so they must be different radiators; you are supposed to have increased cooling with the tow package.
Yet GM openly advertises that as part of the towing package one gets a transmission cooler so why wouldnt GM also make it known that there is a more robust i.e larger radiator ???
 

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Discussion Starter · #15 ·
Blue_2009_SLT2 said:
LOL sometimes we have to unplug to understand things. I'm sure HD (high def) has replaced heavy duty for many people in this electronic age of not only hi def video but high def audio as well.

Anyhow, I looked here:
http://www.autoguide.com/new-cars/2009/gmc/acadia/sle1/specs.html
2009 SLE:
Front Brake Rotor Diam x Thickness (in): 12.8 x 1.1
Rear Brake Rotor Diam x Thickness (in): 13.0 x 0.8

http://www.autoguide.com/new-cars/2009/gmc/acadia/slt1/specs.html
2009 SLT1:
Front Brake Rotor Diam x Thickness (in): 12.8 x 1.1
Rear Brake Rotor Diam x Thickness (in): 13.0 x 0.8

They didn't have listings for the 2007, so I looked here:
http://www.autoblog.com/2006/07/12/2007-gmc-acadia-revealed/
front: 12.8 x 1.1 / 325 x 29, ventilated
rear: 13 x 0.8 / 331 x 20, ventilated

Summary: All dimensions are the same, and I didn't see any mention of tow packages changing this.

When auto makers have offered two or more brake options on vehicles, this is usually due to a higher gross weight (GVW) rating (usually trucks- Sierra 1500 will have smaller brakes than Sierra 3500) or high performance models (i.e. larger motors). Again using the 2009 Challenger as an example the 6.1L V8 SRT8 model has larger rotors (14.2") than the R/T, and the 5.7L V8 R/T has larger rotors (13.6") than the 3.5L V6 SE (12.6"). The 2010 Camaro is similar (but has big brakes in all V8 trims :thumb:). It would be odd to me for GM to make two different sizes of front & rear rotors for the Lambda since there is no variation in the GVW and they all have the same motor.

Let us know what you measure on both.
Okay, the disks are the same and the front calipers look the same, but the rear calipers look bigger on the 09. The online gm part store only shows for the 07 and 08's. Where would I find info on the 09 calipers. That is what I was really refering to when I said they look bigger and I was not clear enough on that.
 

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We have some members that have access to GM parts info, we'll have to wait for one of them to jump in w/ any parts info for the 2009 model. Based on what tm59 posted, it sounds like the parts (pads) are the same, so any difference in the calipers would be styling only.

On a front engine (weight biased) vehicle, a larger swept area (caliper & pads) would be of greater benefit on the front vs the rear.
 

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It will be interesting to find out if GM has changed piston size in the '09 tow package rear calipers and kept the pucks and rotors the same. I would think more brake application would be needed to the rear wheels if towing a loaded trailer that's not equipped with its' own brakes. This might be true especially for FWD models to maintain greater stability under braking.

Does that make sense to anybody?
 

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speleos said:
It will be interesting to find out if GM has changed piston size in the '09 tow package rear calipers and kept the pucks and rotors the same. I would think more brake application would be needed to the rear wheels if towing a loaded trailer that's not equipped with its' own brakes. This might be true especially for FWD models to maintain greater stability under braking.

Does that make sense to anybody?
:tard:......................I get it, but I think it may be a stretch for GM to make those kind of changes IMO of course
 

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khansen30 said:
Engine - no comparison! I only have to put the pedal down half way to match flooring it in the 07. I can tell the difference in the DI. More power, quieter sound, and more responsive. MPG is not much better in the city for me. First 2 tanks were 13.5 (not much in the way of highway, all stop and go (lights)). Taking it on the road for a 1000 mile test this weekend, so I will see how it does on the highway.

Transmission - no comparison! I had the 2 flashes on my 07 last one being last May. Never would go into 6th on the highway unless I tricked it. Lots of shifting. Shifting is smooth in the 09. A side from the learning process (it learning, not me) the feel and response time is great. When I have had it on the high way it shifts smooth and stays in 6th like it is supposed to.

The overall feel and ride is much better. The bigger breaks (because I have the towing package this time) make a big difference in stopping as well. Smooth and soft, no gripping that I had before. No more squeeky pedal. No steefing noise.

This was a great decision to get out of the 07. The only thing I don't like, well actually 2, is no heated washer fluid - oh well, never worked well anyway, and the leather on the steering wheel and shifter feels synthetic and not like real leather. I think they saved money by going to a split grain that is tanned cheaper - although it is still leather.

Love the 09 - Love the Acadia! :thumb:
Since I'm an 09 Lambda owner, this is nice to hear....glad I held out for the 09's. I have to question one thing here: You, along with others, have mentioned that these transmissions "learn" driving style. At least, that's what I think you meant. Do you, or anyone else have this in writing somewhere, that explains this? I've asked this before, and no one has provided any proof that states these trannys learn. I had read about a Cadillac transmission, I think also a 6-speed, that would do that...but nothing about the Lambda trannys. Just curious if this is in fact true, or myth.
 

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A learning trans? That's a new one for me; I sure would like to hear this
 
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