We tow a Alpenlite with a certified dry weight of 9300 pounds. On six percent grades in the Southwest my best speed is thirty miles per hour. On level stretches the Duramax performs well. Should we expect higher speeds on these grades?

I woud think so. How many miles on your duramax? Have you ever changed your fuel filter?

I pulled my 28ft. 5er up a pretty good grade in Montana and had more power than I needed. You have some kind of problem. My Duramax only had 4,000 miles on it at that time. Like Max Power said you should check your fuel filter. You never mentioned the year model and milage on your Duramax.

What's your altitude? Could you explain what a 6% grade is? How many degrees? If I remember correctly 6-7% grade is about as steep as highways can be?

fisherman-


You defanitly have a problem with either your truck or your trailer if you can't pull that little trailer over 30mph on a 6% grade. I have yet to find a hill I can't pull at a min. of 65mph. Last May I pulled my 36' 16,500lb fifth wheel from Las Vegas to Reno, where there are lots of 6% grades, even with a stiff headwind I never got below 65mph and averaged around 12mpg. At the time I had no performance modifications and 265-75-16 tires. If your for real, I'd get that thing checked out.





The return trip is a different story as I put 285-75-16 tires on the truck in Reno. There was also 50mph headwind gusts on the return trip, I wasn't very lucky getting headwind both ways.http://www.dieselplace.com/forum/smileys/Disapprove.gif Anyway, MPG went down to about 8 and I really struggled getting up the steep grades, going down to 45mph on some really long ones. Do you run a stock setup? I went back to 265 series tires and the beast is cured.Edited by: neverenuf

The mileage on the truck and the fuel filter are the same-13,000 miles. Dealers in the Phoenix area want over forty dollars for the fuel filter. Tax and labor are additional. Finally found a parts place in Montana that sells Racor made filters for half of the dealer price. Those filters arrived last week but other priorities have delayed my work on the installation. The savings can be used for other needs. Truck is stock. Brakes are not dragging on the fiver.

The Racor made fuel filter has a diameter of four inches but I was not able to find a filter wrench at Sear, Autozone, or Checker Auto Parts that is made for such filter. The largest wrench was a three and seven-eights and will not slide onto the Racor. Where are Duramax owners finding a suitable filter wrench and what type is best?

I use a strap wrench which works well.

snap on has a good filter wrench that is angled. about 20 bucks or so... works good just run down a snap on truck...

I use one of the inexpensive nylon cloth strap wrenches. Most any auto parts store sells them. Edited by: Roegs

I have a large oil filter wrench and I wrap a towel/rag around the fuel filter to take up extra space. Works great.