Last post on Aug 28, 2013 at 6:17 AM
You are in the Acura RDX
What is this discussion about?
Acura RDX, Fuel Efficiency (MPG), SUV
#79 of 223 Re: weighty matters [patentcad1]
Nov 17, 2006 (10:20 am)
I have the Rav4 V6 AWD with 3rd row, that probably adds another 100 lb to it and my worse mileage was 23 MPG. On the interstate I can get 27+ MPG. Hardly the 2-3 MPG you are talking of.
The problem with smaller engines is that they have to work harder and it is a known fact that turbo engines are not really fuel efficient when reving and boosting high. Good examples of smaller vs. bigger is the 2.5l vs. 3.0l X3 or the 2.4l vs. 3.5l Rav4. Both engines get similar mileages.
Having said this, when I kick the Rav4 around town I will get sub 20 mileage too according to the trip computer. You need to cruise in 5th to get 25 MPG or better.
Still looking for a nice car for my wife. Guess the RDX is out of the picture.
#80 of 223 Re: weighty matters [xpander]
Nov 17, 2006 (1:46 pm)
Small engine or large, turbo or normally aspirated, fuel economy is directly affected by power that is being used. Nothing is free, power certainly isn't.
That said, I was looking at reported mileage by owners of various vehicles, and here is what I found:
EPA Rating (City/Hwy/Combined): 21/28/24 mpg
Reported (City 80%): 16.0 mpg
Reported (Hwy 74%): 24.6 mpg
EPA Rating (City/Hwy/Combined): 22/27/24 mpg
Reported (City 83%): 20.3 mpg
Reported (Hwy 80%): 27.9 mpg
The reason I bring this up is to point out how meaningless EPA estimate has become. On spec sheet, it would appear RAV4 V6 is about as good as CR-V I-4 (or RAV4 I-4), but then, where are the results?
Patentcad1, it will be nice if you and other RDX owners will sign up to share mpg numbers on the fueleconomy.org website. The website lacks important details like miles driven, average speed etc, but still provides the best real life numbers.
#81 of 223 Re: weighty matters [robertsmx]
Nov 18, 2006 (8:59 pm)
Here's 1900 miles of real world experience with my new RDX on mpg:
Generally 16-18mpg. I live in a very hilly semi rural area and mostly drive the car locally. As soon as I factor in substantial hwy driving that will start going over 20-21mpg. The car seems to get 21-23mpg on the highway if I drive 65-80mph using the cruise control. My car has the factory roof rack (I currently only have the side rails on) which probably costs me 1mpg or so, more when the Thule rack is strapped on.
My general impression is that if you live in a typical suburban area with a fair bit of hwy driving you may be happy with the RDX mpgs (the car will probably average close to 20mpg under those conditions). All that depends on your expectations. The RAV 4 is a nice car, but would I want a car that gets a few mpg more and give up the RDX's wonderful mojo? Not me.
On the other hand the RDX is a stiff riding car to be sure. Not for everyone. Really loving the car so far. Drove my 2004 TL the other night (which has a much softer ride). The TL is really faster. But I like the RDX cabin/driving experience more after two months. Talk to me a year from now. But the car is doing what I need it to. Swallows up my road bicycle with BOTH WHEELS ON with the seats folded down. Really suits my lifestyle. I'm the guy they wanted to sell this car to. I feel like I got an SUV and didn't give up that sporty handling/drive that I liked in the TL. The RDX actually feels sportier to me (even though it's a bit slower). The whole SH-AWD/great handling/turbo/paddle shifter thing really works for me.
It would appear there aren't enough customers like me out there. Oh well : ).
By the way, I've read a few reports about body panel issues on RDX's. My car seems excellent (no rattles, etc.). Tight as a drum. No issues so far.
I don't think Acura missed the mpg mark on the RDX. Bigger SUV's are generally even worse on gas. Some of the competition may do 10-20% on mpgs - but they're all considerably slower and can't handle like an RDX. Life is a series of compromises. The RDX is just another. By the way, my RDX mpg is almost identical to my pal's Audi All Road (4000 lb. AWD A-6 based wagon).
#82 of 223 Re: What MPG? [exmechanic1]
Nov 19, 2006 (8:41 pm)
I gotta wonder how efficient Acura's SH-AWD system is. AFAIK, none of their SH-AWD vehicles gets very good mpg. So combine a small turbo engine that's always working, plenty of weight and an inefficient drivetrain...
Maybe Honda can improve the mpg before they drop SH-AWD into the next TL/Accord.
#83 of 223 Re: What MPG? [garyw4]
Nov 19, 2006 (11:27 pm)
Today I just test-drove a loaner RDX Tech from the local Acura dealership, on mostly freeway, and very light-footed at 75-85mph: 20.6 mpg. I had the feeling to get a bit better gas mileage when using S mode and paddle shifters, vs the automatic. Gas mileage quickly went into the single-digits on the trip computer when accelerating. Just cruising on the freeway should probably comes out at 20-25mpg. If it weren't for the worse gas mileage compared to my A4, I'd be buying an RDX in an instant.
#84 of 223 Re: What MPG? [garyw4]
Nov 20, 2006 (6:40 am)
I think the SH system is very heavy, which doesn't help. They are primarily using SH-AWD to compensate for the understeer dynamics of the FWD configuration, but you pay for it in weight. Any time you take a FWD platform with a transverse engine and turn it into an AWD vehicle, the packaging gets inefficient and the weight shoots up. If Honda is serious about AWD vehicles, they need to develop a new platform. Only then would they truly see the overall benefits of AWD. Right now, I'd say it's a wash -- you have to trade light weight to get good handling. Can't have both.
#85 of 223 Re: What MPG? [garyw4]
Nov 20, 2006 (7:53 am)
What vehicle(s) are you comparing them to? Acura RL has surprised quite a few people with its mileage. Although rated "only" 18/26 mpg (do people still believe in EPA estimates?), it has been easy to beat the estimates. Even magazines are reporting reasonably good overall mileage with that car.
However, boxy vehicles like RDX and MDX aren't going to return as good mileage. Remember, its not in the turbo, its in the amount of power one uses. It doesn't come for free. Turbo in RDX is delivering as much or better torque than a 3.5/V6, can't expect it to deliver fuel economy of a 2.3-liter engine.
#86 of 223 Re: What MPG? [c_hunter]
Nov 20, 2006 (8:14 am)
SH-AWD is no heavier than competing AWD systems. In fact, it might be one of the lightest, at an estimated 220 lb. And I don't see how transverse layout w/AWD would result in more weight and worse packaging compared to longitudinal layout. Audis, Infinitis and BMWs aren't quite light weight either.
To provide a perspective, BMW 328xi Coupe is 231 lb heavier than 328i Coupe (3582 lb versus 3351 lb). Or you could compare these three:
Acura RDX - 3968 lb (EPA rated: 19/23 mpg)
BMW X3 - 4067 lb (EPA rated: 16/23 mpg)*
Infiniti FX35 - 4268 lb (EPA rated: 16/21 mpg)
The Acura is 100 lb lighter than X3 (* 2006 model), and 300 lb lighter than FX. All three vehicles seem to offer similar interior volume, although FX is larger on the outside. BTW, the FX is also rated worse than the much larger Acura MDX (17/22 mpg).
#87 of 223 Re: What MPG? [robertsmx]
Nov 20, 2006 (9:46 am)
My point is that the RDX would almost surely be lighter if it was not based on a FWD platform with a transverse engine. Nothing about that drivetrain orientation is beneficial in AWD applications -- it only contains penalties. And if it was relieved of the FWD bias with its inherent understeer, the need for the "SH" aspect of the AWD system would go away in large part. I think the RDX would be a better, simpler, lighter vehicle if it started with a clean sheet of paper platform -- not being limited by Honda's reliance on FWD platform engineering.
Yeah, the competition is also heavy (with some notable exceptions in the 3600 lb range) but that doesn't mean Acura couldn't have done better.