CM871 fuel mileage

[Waterloo]

(06-04-2021 )superbudy208 Wrote:  I think a lot of the problem is with the gearing of the truck, @ 75mph it's at 1550rpms in 10th, @ 70 its running 1350 to 1400rpms, and 9th at 58mph is 1600rpms,if I go slower in 10th it lugs it it to much, it does have power its not low well I don't think so anyways, the turbo fluttering almost seems like it popping back through the intake under hard load load sometimes its worse than others, I'm going to run the overhead again and make sure it was done right, I do want to drop the cans but it'll be a week or 2 before I get a chance to.

I've been trying to shift it higher and but it has a problem running in 9th it goes to 1700 and won't go higher then after 15 seconds it slows down to 1500 and you cant push it back over 1600 rpms, I'm going to check with the dealer and see if they can adjust it, I've talked to a few people about programming it, but not really sure I want to go that way.

Also I've called Hagg several times but they never call me back so

I don't really want to do an in-frame on it, that's why I keeps the rpms up but its killing me on fuel and need's the front structure done soon to. Also looking for some 3.55 or 3.73 gears and waiting to hear on a Volvo with a 13 speed that has bad cams trying to figure out which way to go still

Make an appointment with Mr Hagg... They are one of the only shops, and a very small shop, in the entire USA that can consistently repair and rebuild an ISX, they do not have time to call you back. Make an appointment and stick to it. Until then, you are just spinning your wheels and throwing money out the window while pissing the rest away. You have too many things going on with this truck to simply say go get an Inline reader and do this. You have multiple issues, all from abuse of not properly maintaining and or understanding the proper operation of an ISX. If you cannot get to Mr Hagg, your best bet is to off load that truck. The one with the bad cams... Are you serious?