Product improvement idea for the H3

[Huck BB62]

I'd like to see ALL of the GM products do this: Kick the vehicle out of 4 wheel drive when it hits 55. I'm serious. I use 4 wheel drive every day to avoid damaging our 500' 16% grade gravel driveway. This morning, I drove 45 miles to work in 4 wheel drive. I didn't notice it until I turned into the driveway at work and felt the steering. It's easy to do. My wife's done it twice in our Sierra, twice in our last Yukon and now this one. I don't know how hard it is on it, but it can't be good. There's at least half of the trip over 70mph. Egads, what have I done to our new H3?

[Huck BB62]

I'd like to see ALL of the GM products do this: Kick the vehicle out of 4 wheel drive when it hits 55. I'm serious. I use 4 wheel drive every day to avoid damaging our 500' 16% grade gravel driveway. This morning, I drove 45 miles to work in 4 wheel drive. I didn't notice it until I turned into the driveway at work and felt the steering. It's easy to do. My wife's done it twice in our Sierra, twice in our last Yukon and now this one. I don't know how hard it is on it, but it can't be good. There's at least half of the trip over 70mph. Egads, what have I done to our new H3?

[Steve - SanJose]

The Marketing guys in GM will never let it happen in their lifetime. All Wheel Drive is a heavily promoted "safety feature". Not having the perceived safety of All Wheel Drive at speeds over 55mph would not be a good selling point.

Note: H2 is "full time 4wd" also

[Surferjo]

Im not sure i follow but do you mean kick out of locked 4WD high?

[Steve - SanJose]

Oh now I think I get Huck's concern. I think he experienced his transfer case hanging-up in 4 wheel hi-Locked, after he pushed the button to switch back to 4 hi-open (leaving the center diff locked).

The manual addresses this topic somewhat, but Huck does bring up a good point.

[Steve - SanJose]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Steve-SanJose-H3:
Oh now I think I get Huck's concern. I think he experienced his transfer case hanging-up in 4 wheel hi-Locked, after he pushed the button to switch back to 4 hi-open (leaving the center diff locked).

The manual addresses this topic somewhat, but Huck does bring up a good point. </div></BLOCKQUOTE>

Or maybe even worse, Huck forgot to switch it back to 4 hi-open. Regardless I think Huck is suggesting that it should automatically switch back to 4 hi-open at 55mph to minimize wear on the drivetrain. Probably not a bad idea.

[f5fstop]

First, let's understand there is a difference between, all-wheel drive, part-time four-wheel drive, full-time four wheel drive.
In an all-wheel drive system, a small percentage, usually around 10-15 percent is directed to the non-drive wheels. If there is slippage detected, up to 50 percent can be directed to the non-drive wheels. This can be done mechanically or electronically, and the actual percentages can be different depending upon the manufacturer.
The H3 does not have what is known as a all-wheel drive system. It has a full-time four wheel drive. In non-lock, there is 40 percent power to the front, 60 percent to the rear.
Lock the case, and it will go to 50/50.

(We should all know the difference between full-time and part-time four wheel drive.)

As for the initial concern, if GM programmed it to unlock at 45 and someone needed it at 50 (for example), they would be upset.
Hate to sound sarcastic, but that is what the lights are on the dash board for; to signify if you are in open or locked 4-wheel drive operation.
I guess they also expect those who engage 4-wheel lock, know that they have to turn it off.
As for damage, I would bet you did no damage to the case.

[Steve - SanJose]

The issue really is increased wear on the drivetrain (not damage as you pointed out) if left locked for extended periods at speed on dry pavement.

[Huck BB62]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Steve-SanJose-H3:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Steve-SanJose-H3:
Oh now I think I get Huck's concern. I think he experienced his transfer case hanging-up in 4 wheel hi-Locked, after he pushed the button to switch back to 4 hi-open (leaving the center diff locked).

The manual addresses this topic somewhat, but Huck does bring up a good point. </div></BLOCKQUOTE>

Or maybe even worse, Huck forgot to switch it back to 4 hi-open. Regardless I think Huck is suggesting that it should automatically switch back to 4 hi-open at 55mph to minimize wear on the drivetrain. Probably not a bad idea. </div></BLOCKQUOTE>

Exactly my point. I can't think of a reason for 4hi lock to be engaged at freeway speeds, particularly since it's not good for it.

[Huck BB62]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by f5fstop:
First, let's understand there is a difference between, all-wheel drive, part-time four-wheel drive, full-time four wheel drive.
In an all-wheel drive system, a small percentage, usually around 10-15 percent is directed to the non-drive wheels. If there is slippage detected, up to 50 percent can be directed to the non-drive wheels. This can be done mechanically or electronically, and the actual percentages can be different depending upon the manufacturer.
The H3 does not have what is known as a all-wheel drive system. It has a full-time four wheel drive. In non-lock, there is 40 percent power to the front, 60 percent to the rear.
Lock the case, and it will go to 50/50.

(We should all know the difference between full-time and part-time four wheel drive.)

As for the initial concern, if GM programmed it to unlock at 45 and someone needed it at 50 (for example), they would be upset.
Hate to sound sarcastic, but that is what the lights are on the dash board for; to signify if you are in open or locked 4-wheel drive operation.
I guess they also expect those who engage 4-wheel lock, know that they have to turn it off.
As for damage, I would bet you did no damage to the case. </div></BLOCKQUOTE>

The lights on the dashboard are small. One looks the same as the other when you get in after a nights sleep. You start the H3 and drive. I put it in 4lock to minimize the damage on the driveway and park it. I get in in the morning and drive to work. I use 4lock every single day. 99% of the time, every time until today, I remember to put it back when I hit the pavement. It seems funny to me that you get this big screen flash and it's own symbol when you de-activate the traction control but nothing but a wee little light on the next switch over when it's in 4lock. The tire pressure monitor gets all over your dash when it's cold. Leave it in 4lock and drive 85mph, nuttin'.

My tcase works fine, it just sounds louder when I tried it in 4lo lock on the dirt road when I got in the oil field. Time will tell.