You are here: Forums SUVs GMC Acadia GMC Acadia Real World MPG

GMC Acadia Real World MPG

61 messages,  Last post on Nov 16, 2009 at 2:00 PM

You are in the GMC Acadia Forum. Your Hosts are steve_ & tidester

What is this discussion about? GMC Acadia, Fuel System, SUV

Messages Page 7 of 7 1 2 3 4 5 6 7 Prev Next Last

Go To Msg # Search This Discussion

#58 of 61 Re: Gas mileage experiance? [lukesdaddy] by acadiaregret Aug 03, 2009 (10:49 am)
Replying to: lukesdaddy (May 12, 2007 4:47 am) I have an 08 AWD Acadia and I get 10 mpg city / 14 mpg hwy Replies to this message: stdavis (Aug 03, 2009 12:01 pm)
#59 of 61 Re: Gas mileage experiance? [acadiaregret] by stdavis Aug 03, 2009 (12:01 pm)
Replying to: acadiaregret (Aug 03, 2009 10:49 am) If you find any solutions let me know GMC sure doesn't have any. We have never achieved anything better the 12.5-13.5 in town with very little mix of highway and 17-19 on the road. Makes me regret trading the 99 Tahoe that did better and had much more horse power and performance. At least I knew I was giving up fuel economy for performace with the Acadia I get neither. All GMC could offer was keeping the Nitogen pressure (which is a joke as far as I can tell) in the tires at 38-40 and using 100% gas with no ethanol. I think this results in about 1 mile per gallon difference. There where rumurs that GMC would come out with a better automatic shifting algorithm for the transmission, but I have never seen it.
#60 of 61 My experience by loach Aug 03, 2009 (1:23 pm)
Now that my '08 AWD Acadia is broken in, we've been getting mostly 13-14 MPG city and 20-24 MPG highway depending on conditions. We've never come close to getting the 16 MPG city EPA rating, but easily beat the 22 MPG highway rating if the conditions are favorable.   I consider these numbers to be well within reasonable tolerances. The Acadia is a bit of a pig in stop and go traffic, but really shines on the highway for a vehicle this size.
#61 of 61 MPG Explained - 2010 Acadia SLE AWD by victorg009 Nov 16, 2009 (2:00 pm)
Acadia can archive 30-35 MPG under certain conditions, but in everyday city driving it gets 10-15 MPG only. In 1st week of owning I found it has 2 driving modes: power and efficiency. Efficiency is activated only when cruse control is ON or at higher speed, otherwise it is in hungry power mode with loud engine noise despite standard acoustic package and feels like driving a truck (but after a week of driving you stop noticing noise).   When cruse control is engaged, the speed is considered to be constant, and in theory it does not require much power/torque to fight wind/tires drag. Therefore in cruse control the transmission algorithm uses higher gear and lower engine RPM 1400-1600 (2000RPM at 65mph). On the flat road ODBII scanner shows instant MPG 35+ at 40mph, 30MPG at 65mph and slightly less at higher speed.   It takes lots of gas to accelerate 3 tons on metal, plastic and rubber, or drive it uphill. Therefore during acceleration/uphill MPG is never above 10, and can be even lower. The only way to increase fuel efficiency for acceleration/uphill is to change driving habits. Buy PLX Kiwi OBDII Scanner and Fuel Saving Device. As for me Acadia proved that I need PLX Kiwi and I will be getting one.   Now to the root of low fuel efficiency problem. When not using cruse control at low speed 25-40 mph, transmission algorithm uses lower gear to run engine at 2000 RPM or slightly higher, and car gets about 15 MPG. Engine noise gets louder too. On cruise control on the same road it runs engine at 1400-1500RPM, and about 25 MPG. Efficient lower RPM program handles constant speed even with some uphill/downhill without any problems (ODBII scanner shows good MPG drop when going uphill on cruise control).   My 2005 Camry drives at reasonable 1200-1500RPM at lower speeds on flat road, and I believe that Acadia engine can still provide enough power at 1500RPM. I am going to dealer to have transmission reprogrammed to shift to higher gear sooner to match driving with cruise control ON.

Messages Page 7 of 7 1 2 3 4 5 6 7 Prev Next Last

Go To Msg # Search This Discussion

You are here: Forums SUVs GMC Acadia GMC Acadia Real World MPG