Few Denali Questions

[GM Customer Service]

Mr T,

Unfortunately, your Yukon XL Denali does not have active fuel management. This was first offered on the 6.2L engine in the 2010 model year. Your Yukon would be AWD. The all wheel drive system will kick in when needed to help with traction issues. I will check on your third question and I will get back with you when I have found an answer.

Thank you

Elizabeth, GM Customer Service

 

[phileaglesfan]

I agree with Elizabeth above. My 09 does not have FMS but the 10 does. From what I have seen with GM's FMS on other vehicles (Envoy/Impala) you pretty much have to be cruising on an extremely flat road for it to engage into V4 mode or going down hill. I just returned from a long road trip and I averaged 17-19mpg cruising at 70-80mph. Worst was 15.2 driving into a strong headwind at 80mph in Wyoming.

I can tell you from driving in deep snow that the AWD system is perfect for on road conditions. Due to its high clearance it is also higher off the ground compared to most AWD sedans.

If my kiddies are watching a movie in the back I can do anything up front besides play a CD (since the DVD is in that slot). In my 09 I bought an IPOD lockpick so I can use my IPOD. A stock system should be able to play XM/AM/FM . Separate audio controls in the back allow for them to play a different system also.

 

[Mr T]

If my kiddies are watching a movie in the back I can do anything up front besides play a CD (since the DVD is in that slot). In my 09 I bought an IPOD lockpick so I can use my IPOD. A stock system should be able to play XM/AM/FM . Separate audio controls in the back allow for them to play a different system also.

Phileaglesfan: Thanks for your reply. Let's say they have a movie in and I want FM radio (or XM), how do I make that happen? Also, I assume they are using headphones so the SUV is quite to begin with.

Elizabeth, GM Customer Service: Thanks for your contribution. You've put that question to rest.

 

[GM Customer Service]

Mr T,

You’re welcome. I am very happy to help!

Thank you

Elizabeth, GM Customer Service

 

[Zed 71]

Btw, another difference between AWD and Auto 4/2WD is that although the AWD has better overall traction over all road conditions it does no offer the 4WD Low setting. Basically completely different system for different uses ... AWD for overall better traction, 4WD/2WD Auto most of the time is in 2WD and 4WD is available when needed.

Well, AWD does offer better traction on road versus 4WD (should not be used during most conditions). However, off-road is a different story.

Typically all four wheels in a full time AWD system are connected by differentials. When a wheel loses traction, potentiall all of the power goes to that one wheel (this is without traction control) while the other three sit stationary (torque reduction condition) . Yes traction control will help, but it does so by reducing engine power and/or applying brakes.

The part time 4WD system uses a transfer case, and subsequently does not suffer any torque reduction. If a front wheel loses traction, it does not reduce power to the rear tires. This is not even taking into account the lower gears.

I know this thread was not AWD versus 4WD, but I just wanted to throw in some information .

 

[mike1944]

My two cents on FMS (2010 Denali):

Just got back from a long trip from SoCal to Florida and points in between. On those long desert stretches.....Texas is too #%^& big....watched the FMS and found the following.

If it was flat, and I kept the cruise control speed to about 45 or less, the V4 would kick in and stay on for some long stretches.

45 to 65 or so, the V4 would occasionally kick in.

Anything over 65 the V4 rarely came on except for some downhills runs.

Any uphill, no matter how slight, would kick it out of V4.

As I've mentioned elsewhere I averaged 18 for the whole trip. Some parts I was getting 19 plus.

 

[Mr T]

Thanks for those details, Mike. Very interesting to see. Wish I had it but fully understand I can't. I think I'd save a few MPH on occasion. However, if it was a "feature" you could pay for when buying, I wonder how many would pay say 1k or so for it? I don't know if you'd get that back in anything less than 50K of freeway miles. I'd need to do the math on a spreadsheet to find out.

 

[aak274]

The transfer case in the 07+ Yukon Denali and Escalade isn't a viscous clutch system. Its a planetary differential system that acts much like an 'open' differential... I can only assume they did this to save cost, because this system relies on the brake traction control system (Stablitrak) to transfer power between front and rear axles and side to side... except in the rear because all AWD Denail and Escalades have rear locking differentials aka Eaton G80 (youtube it)

The AWD system in these trucks work great on dry/wet roads but in snow they leave a bit to be desired. My Envoy with its lockable 4x4 system will outperform our Denali and Escalade in the deep snow. The AWD system in these trucks are less predictable in the snow than a 4x4 as well. I notice the Yukon likes to hang its ass out when getting into the throttle on snow covered roads... Unlike the Envoy that stays planted until all four tires break loose... It seems like the rear tires on the Denali will break loose first.... which makes sense because the transfer case is 'open' there for sending power to the axle with the least resistance (normally the rear because the ass end is lighter) YMMV. I live in upstate NY... Heavy snow for us is 18" +

The 08' does not have AFM either.... I think they put that on the 6.2L in 2010 and they make it a flex fuel motor in 09'..

You can listen to a music in the front of the truck when someone is using the RSE provided they are using the headphones...

Hope this helps... Enjoy the truck man, I love mine

 

[Mr T]

Man I love this forum. Just learned what a Eaton G80 is and I'm impressed. What i can't figure out is why hasn't ford and crapler done something similar by now. You would link they would realize a limited slip differential isn't all that much better than an open one. I remember, as a kid, many times having to pull or push an uncle or other family member out of a jam when they'd get such slip.

As for what is better in the snow and not, I'd probably agree the 4X4 is ideal as it provides more control; however, our Denali is primarily my wife's vehicle. I'd rather have her in a AWD since I don't need her flipping a switch when she hits snow or slick spots.

Again, thanks for the technical answers. Just what I was looking for.

 

[soulsea]

I'd rather have her in a AWD since I don't need her flipping a switch when she hits snow or slick spots.

Actually just to clarify ... if it were a 4WD like my Tahoe, Mrs T wouldn't have to flip any switch when she hits snow or slick spots as the Auto setting does that automatically, although admittedly, not as fast as a full time AWD vehicle does.

What we with 4WD sacrifice in overall traction, and inability to engage 4WD on dry pavement, we gain by being able to manually keep the vehicle in 2WD should we wish to save fuel, the ability to use 4WD Low, and the ability for better deep snow/off road capabilities.