Would appreciate any reviews or opinions on Cummins ISX. I am interested in getting one. Also, it has auto transmission (Freedom Line).

Thank you.

 

The truck I bought has both (Cummins and Freedomline) Had 500k miles when I bought it 7 months ago and I have put 80k miles on it.

The ISX is ok except the parts are expensive to replace. I replaced the EGR valve and Turbo a few weeks ago and it cost $3800.

I get good fuel miles and plenty of power with the ISX

I have driven both the Freedomline and the Ultrashift and the Ultrashift is way better. The Freedomline shifts sloppy to me compared to the Ultrashift. The first week I had my truck the clutch went out on the Freedomline and it cost almost $4,000 to replace.

 

I have a 2006 International 9900 with a 500 HP ISX.

My two previous trucks had Cummins N14's.

The ISX is a significant improvement with power, fuel economy and with hold back on the Jake.

I run 80,000 lbs, but have had it pulling chip trains that grossed out over 140,000. In the fleet it was leased to, it outpulled every other truck they had, and every driver saw it when we passed them loaded on the big hills. We could pull one gear higher than most other trucks, especially the Mercedes engines. We could decend one gear higher than the Cat engines and still not touch the brakes on the 8% grades.

It has 80,000 miles on it, and I had to do the Turbo just last month. It cost about 1,000 as the new ones have a kit available for them. I paid over 3 grand for a turbo on the N14.

I like it. If I where to purchase a new tractor, I would get another one.

 

I had 2 KW T2000's with auto and an ISX in each. Ran 2250 miles each week with 40,000 to 44,000lbs of paper. In the summer I avgd about 7.2 - 7.4 and the winter around 6.4mpg. of course, I didnt idle the truck as we had bunk heaters and in the summer I was north of the Great lakes so didnt need the A/C. I liked the power and never had a problem with the engine in any way. And once I got used to the Autoshift I loved it.

 

2008 model year, 486 hp, T660:

Fuel mileage is disappointing. Toronto to Syracuse at 80K gross then back to Toronto empty resulted in 5 mpg. Doesn;t seem to matter if you're driving 72 or 62 mph. Pulls good though.

 

Sounds very low. I get 7.5 mpg (imperial gallon) running 75,000 in the mountains.

 

Wish my signature 600 would have done 5.5 mpg. I'd have kept it. AWESOME engine.

 

UPDATE: It now has a new turbo at 120,000 miles. Covered by warranty, but still. What a joke.

 

I’ve got a 450HP ’06 ISX with an Autoshift (only because the wife is too lazy to actually manually SHIFT a truck). I love the fuel economy compared to my C-15, but if I could get my old ’03 500HP C-15 back and have the same 6.75 mpg I’m getting now I’d do it in a heartbeat. My old CAT would way out pull my new truck. Not to mention that I’m bothered by Cummins’ belief that 35 psi oil pressure is adequate… every time I start my truck up I wonder what the heck they were smoking when they came up with that one.

Besides the fuel economy, the only positive comment I can make about the ISX is it has one hell of an engine brake. Cummins doesn’t use a Jacobs Vehicle Systems engine break, but rather their own integral engine (they call it an “interbrake”) brake that they claim offers the same braking horse power as driving horse power. I’d have to say that they are accurate in their claim. We run out west a lot (and up and down I-5) and I can probably count on one hand the number of times I’ve had to use the service brakes when descending a hill in our new truck.

 

My '01 ISX has nearly a million on it, though it had work done on it at 650,000 before I bought it. It's been great for me, I add no oil between changes for one.

This is what I want to say, though: A $9.99 12volt air compressor can really improve the quality of life for an ISX owner. If you don't know why, just ask, I'll elaborate! :smokin: Man, I love that pump!