Re: cat c15 emision engine with cx31 trans VRS ISX cummins with alli
Reply #6 –
Yahoo Message Number: 92344
Hey Bert - Out of curiosity, what speed were you able to maintain towards the top, just before the level off into the tunnel? Was this East or West bound on I70? (And I know that driving conditions can result in needing to slow down for say slower big trucks. Do you recall if this took place, or did you have a pretty clean run?)
We just came back West towards the tunnel, about 6 weeks ago. Our 40', Tag, lighter then the Magna coach. With ISL370 was down in third gear most of the last mile of the climb and keeping 35-38MPH. It did hit 2nd and down to 30 or so MPH right at the very top 200' or so. (We were fully loaded with new full fuel tanks, and due to the National Park shut down, I had also topped the water tank in case we had to dry camp, so we were heavier then we normally travel. Small CRV with full fuel also as the toad.)
The ISL does us very well 98+% of the time, but it is sure working hard at a time like climbing the I70 grades:)! This is the CAPS era ISL, and I understand the higher boost spooling ISL400 with VGT does a bit better at pulling.
Just wondering how that BIG CAT took care of you, factoring the heavier coach and engine and trans (Assume the trans is heavier then the Allison MH3060? May not be...).
Oh, and our two stage Jake in High and in 3rd or 2nd (started in 2nd, moved up to 3rd part of the way down the long grade on the Western side of the tunnel. I did touch the service brakes a few times in 3rd, but was very pleased with how it went down the hill.
Appreciate info sharing!
Smitty
04 Allure 31010, 40' Tag, ISL370 CAPS