As of now I have no O/D disable or T/H mode, dealer ordered part won't be here until this week. So......this past weekend I took the 8,000lb. 5th wheel out about 200 miles through hills and mountains. A few of the big passes showed 5th gear, no converter lock, about 45-50mph, egt's to 1250 but not sustained more than a few seconds. The truck would still hold mph's, but with no lock out you could really hear the engine working. I kept thinking to myself, "Tranny slip, tranny slip, tranny slip" all the way up the hill. When it got to be too much to handle I would either back down throttle or hit it hard so it would downshift to 4th and lock. Never noticed excessive tranny temp though. Engine temp rose a bit also, but not too bad.


So my question is could I have hurt anything by allowing this to happen? At this point I'm not too worried, as I know this is a tough truck, but I started reading some of the posts about towing and O/D and excessive heat etc., and am starting to wonder. I'll have the T/H working before my next trip, but do any of you think I might have jacked anything up for the long term here?


BTW, heavy go pedal with no load usually locks converter anyway by 3rd gear. I noticed with 5er on, when going up hills and hitting throttle pretty good, it would not lock or downshift. I had to basically go to WOT to get it to downshift. Is this because of the juice? I thought I read somewhere on this forum that the juice kind of tricks it into staying in 5th gear because of the extra power. Also, would the egt's and engine temps stay lower if the converter is locked going up those big hills? The few times it stayed locked in 4th gear it seemed to have more power up the hills with less egt's - just my imagination here?


As usual, thanks for any input. Sorry for all the questions, I've definately still got a lot to learn here......


HD

First I have to ask ,why no Tow Haul mode ??


If your running the Juice on the lower settings IMO the only thing that would be slipping is the TC as it would stock in this case also ,unlocked ...Unless you were seeing some rise in tranny temps I wouldn't worry ...





The Duramax is working and reeving as you describe is normal and what the Juice will do is add some torque and allow the holding of a higher gear longer before a down shift is forced ... This will in most cases help fuel economy and drivability ...





Mac

Thanks for the input Mackin,


T/H started having problems one day. For a while there it was intermittent, seeming to work when the engine was cold and stopped as it got warmer, then it just quit working all together. The dealer is ordering me a new switch in shift lever. That's how the invoice states it. They didn't know how to correct the problem and had to call their tech line. GMCSID said that was probably the problem before I took it down there, so I'm happy with their decision for now, but it always worried me when they don't know the truck real well and now they're gonna tear it apart and try to replace parts. I'm just thankful it's not a serious tear down of the engine or something, that would really freak me out.

Changing the shift lever is simple ..... I replaced mine with a Escalade lever ....





Mac

On a stock ALLI the clutch packs will have more psi with the T/H off. It dumps some pressure when the T/H is on. I wouldn't be too worried.

Thanks for the replies. Less worrying for sure now.


We'll see about the shift lever. Mac, when you coming to Reno? I'd rather have you work on my baby than those wretched souls at the dealership.http://www.dieselplace.com/forum/smileys/Big Smile.gif

The little orange wire finally broke on mine 2 months ago. It broke at the junction a few inches out of the lever. I removed the rubber booth with some dish soap and was able to repair it with a few layers of heat-shrink. Worked fine since then. That lever must be expensive.