I drive an '06 Volvo, with a 475hp ISX, 18-speed, and 4.11 ratios. The average weight ( GVW ) I pull is 37,000 kg ( 81,000 lbs ) when I'm pulling a 5-axle, and 63,000 kg ( 138,000 lbs ) when pulling a super-B train.

When I pull a 5-axle over a hill, I don't need to drop even half a gear ( our trucks are governed at 100 km/h, and I usually drive at a speed of 95-98 km/h ), and 8 times out of 10, I leave other trucks who may have passed me earlier, in my wake. A really big hill, like Big Smoky ( on the way to Grand Prairie ), sees me drop down to maybe 7 to 6 over, from 8 over.

When pulling a super b, i may need to drop down to 7 or 6 over on regular hills, and to around 5 or 4 over on really steep climbs. I still end up out-pulling most other trucks, but they end up passing me on level terrain, since I don't drive too fast.

 

you guys must have super c-rummins isx versions in your rigs to be pulling big hills at 80k with great speed ...to me a big hill is no less than 5-6 % .... :wink: Because the 600 HP ISX that was in the T-600 I had was a dead dog...the reason people see this motor pulling harder with a load is thats how the variable boost turbo is set up to work . but i'll give this motor the benefit of the doubt ,as the company that owned this truck really pushes service intervals ,and it was well over due for a basic oil/filter change and i'm positive it needed an over head...heck the truck i currently have with them only has jake break working well in 9th/10th with sometimes in 8th and nothing below ...can't get approval to take it in to a shop...it has 117k on the odometer and was due for service at 107 k ...can't get approval to take into shop...most cats get an overhead between 40-60k during initial break in ,and i remember this being done on every werner truck with a c-15 as part of compliance with the cat warranty ,however when i mentioned to road breakdown that my check engine light is on they said just keep driving ,and i inquired about when it had it's overhead done ...they laughed and said it only has 117k on it ...this cat only has 117k the cummins had about 600k on it ,so i guess it's fair to say with a maintinence program like this and 600k on the clock it might not have been tip top .

 

Is this a Signature 600?

 

Just because it's rated for 600 HP does NOT mean that's how much power it's tuned to put out!

My Freightshaker has a Detroit series 60 motor in it, and it says 515 HP on the motor...

But my company, like most out there castrated this baby when it was new....it is NOT belting out 515 HP!!!

It was most likely turned down for fuel efficiency...

 

The ISX "recommended interval" for overheads is 500,000 miles.

I think you had a serious mechanical problem for it to be that gutless, most guys I talk to say their ISX has some good power.

 

Well that RED motor had over 600k on it the check engine light was on constant as well ...As for overhead intervals on this motor it was at about 600k and I'm positive it never had one ...Now for cat I'm not sure what the intervals are I just know that as part of the warranty on the cat motors werner had to have their trucks in to a shop or have tha cat mechanic doing an overhead between 40-60k to not have their warranty voided .

 

I just had a sim prob. It was the VGT valve. Has something to do with the waste gate on the turbo. Anyway it had a small leak and was killing the engine. Would climb fine with 40k plus but acted like I was pulling with my pickup when under that. It may also be a programing issue.