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jhan
09-10-2009, 12:11 AM
Hi,
I recently took a trip from Los Angeles to Yosemite, San Francisco, and Santa Barbara while towing a 2007 Honda Odyssey on a tow dolly.
I could barely go up some of the hills. I had to down shift to 3rd gear while going about 35 MPH. Is this normal?
I do have to say, my temperature gauge was fluctuating quite a bit. It also over heated a few times while climbing the CA-140 going to Yosemite. But again, it was one of the hottest days, so I'm assuming it's 'normal'.
I called one of the Freightliner facility here in So Cal, and they wanted me to pay a few hundred dollars to see what the problem might be, and it will go toward the cost of fixing the problem, if there is one. I was also told by a neighbor that I can 'up rate' my C-7 to 350HP from 300HP, but I might start to have over heating issues.
Any comment/suggestion is appreciated.

Fl Mike
09-12-2009, 11:50 AM
I have the same unit, but have not been in the mountains of the West, only the Smokey Mountains. I was pulling a 7 X 16 trailer with two motorcycles in it and did not have the experience you are describing. I would downshift but maintained plenty of power. My former RV was a gasser and did have some real problems with some of the mountain roads.

I wish you luck and will be watching to see if you get some helpful information. We have a trip planned throughout the west in June....

Michael

micacrumb
09-12-2009, 06:02 PM
usually under the conditions you are described it could be a couple of things you need to check, the air filter for dirt or obstruction, In my 02 Beaver with a 300hp cat we had a swallows nest in the intake of the air filter. The other thing is to check both fuel filters one for water and the other for the dirt. I'd change both if it hasn't been done with the last oil change or the last 6 mo. Hope this helps.

micacrumb
09-12-2009, 06:07 PM
I forgot one thing I'm not sure if the newer Cats have the same problem, but the breather for the engine emits some oil droplets and that blows back on to the radiator and in turn collect dirt on the radiator which eventually clogs the radiator causing over heating.

rdlamb
09-13-2009, 08:19 PM
Jhan:

There is an electric module that controls when your auxiliary cooling system comes on.
Check out this thread, and the sites I recommended. I'd think the sites will answer your question of overheating.

viewtopic.php?t=1771&highlight= (http://www.gsowners.com/viewtopic.php?t=1771&highlight=)

jhan
09-15-2009, 12:47 AM
Thanks for all the response. The coach was service right before the trip. As far as I know, both fuel filters were replaced. I will check the air filter when I get a chance. I did notice the drain hole plug for the air intake was missing. It's located at the elbow going to the top of the back of the coach. I got a 1/2" plug and plugged it up. Not sure if that will fix anything.
I read about the breather valve, but I'm not sure about what I've read. I'm assuming the oil gets sucked back to the radiator, so I should clean the side (facing me when look from the back)? Because the "back" side is very close to the engine, and I'm not sure how I can clean it. There is also another 'radiator' infront of the rear wheels, I'm assuming that's the intercooler for the turbo? Thanks for all the help, again.

PChez
09-27-2009, 01:06 AM
Hi,
I recently took a trip from Los Angeles to Yosemite, San Francisco, and Santa Barbara while towing a 2007 Honda Odyssey on a tow dolly.
I could barely go up some of the hills. I had to down shift to 3rd gear while going about 35 MPH. Is this normal?
I do have to say, my temperature gauge was fluctuating quite a bit. It also over heated a few times while climbing the CA-140 going to Yosemite. But again, it was one of the hottest days, so I'm assuming it's 'normal'.
I called one of the Freightliner facility here in So Cal, and they wanted me to pay a few hundred dollars to see what the problem might be, and it will go toward the cost of fixing the problem, if there is one. I was also told by a neighbor that I can 'up rate' my C-7 to 350HP from 300HP, but I might start to have over heating issues.
Any comment/suggestion is appreciated.


I think the problem with your coach if it has felt under powered since new is that you might need the computer reflashed. The C-7 engines had that problem when they were first introduced as the C-7. They used to be called the 3126-E with 330 hp. I climbed the mountain going to Yosemite on highway 120 out of Manteca, Ca. There is a stretch twelve miles long going at about a 8% grade with lots of switch backs. By the time I got to the top pulling a 4400 lb toad, the temperture had gone up some. But it is perfectly normal, all you have to do is keep your rpm up at around 1900 and you will be ok as far as the overheating. But if you lug the engine that is not good, it will overheat for sure.