We live in the Sierra Mountains of Northern CA. We tow a 12,000 pound fifth wheel (Grand Design 303RLS). We tow mostly in CA, NV, OR, WA, MT, ID, and CO. We tow with a 2021 Chevrolet 3500 HD SRW L5P Duramax / 10 speed trans. The hottest I have seen the trans temp is 195 degrees, typically it runs at 147 degrees towing across Nevada in the summer for example. The highest ECT has been 220 degrees (pulling a relentless grade in Northern MT) typically it is 195 degrees. Literally everywhere we go is up or down grade. Assuming you do not have a mechanical problem with the engine (head gasket etc) or a transmission issue and are not loosing coolant it is most likely either poor air flow or a partially plugged radiator that is causing your issue (my educated guess as a retired mechanic not having the option to look at your truck in person). That truck is designed for commercial payload and delivery work not towing heavy, so it may be a challenge to keep it cool. Gear ratios may play a role. Go look at a new GM 2500 or 3500 diesel and note the size of the fan and radiator, you will understand. Please keep us posted on your solution to this issue and absolutely fix this before you head this way. That grade you showed is small compared to what we have out here.
I’ve been around the west twice with my C 4500 change, the oil more often, and I found the shell T6 works. The best on high mountain passes in Colorado. Now that I have 120,000 miles on my truck, I’m using royal purple changing out the oil every 7000 miles I’m at 30,000 pounds just keep your revs up and get that Jake the downhill side get the banks large oil cooler for the engine and then talk to Gary at Black cloud diesel. He has some real special injectors just for towing Keep that radiator fluid in good shape Check your vin make sure that the eighth digit is a 2 there are set up for towing. Starting my third trip around the United States in November this year, I love being retired
I have since added the Banks L5P oil cooler, and switched to T6 and now have an aluminum radiator and bolts thru the fan clutch 🤣 It tows like a dream now!
When I get into the mountains I run the cab heater on high with the fan on high. And open up the windows it will make a big difference on engine heat which also helps the transmission temperature.
I don’t know why I didn’t bother to turn the heat on. I’ve known that helps since I was a little kid but it totally slipped my mind. This setup is very heavy, a bit more than it should be 🤦♂️
I have a 2006 c5500 Duramax class C and struggle to keep temps down when I’m flat towng my Jeep around Colorado. Just out of curiosity, what is your Gross combine weight with that set up?
I would say take a look at their called flex-a-lite fans and the radiator setup they got and I think you need to put an aftermarket transmission cooler and leave the one that's on there but they make them wear their aftermarket and they go under the truck or in the bed and they really help cool my dad used to truck pull that's why I know about these two things that was the only way we could keep the truck cool on the transmission and the motor
We took the scenic route to Rubicon Trail through the mountains. Boy was that a mistake haha. Towing 2 rigs on a gooseneck. Overheated going up, smoked all the brakes going down. Ended up going into 4 wheel LOW in the truck to keep from smoking brakes. Worked well.
I have a 2010 blue bird vision bus with the 6.7l cummins and the allison trans has a sweet vgt exhaust brake and had an idea after seeing a semi hooked to a 5th wheel camper thinking about pulling the bus body off and put a crew cab chevy body and put a flat bed kinda like yours on so I can haul a car on the back and have a goosneck hitch at the back to be able to tow my 35ft 5th wheel on the back just a thought I had think it would be pretty sweet! I have an 05 chevy 2500hd that I have a 12valve cummins nv4500 263xhd in that's my daily driver pulls the camper just fine but would like to be able to take another vehical with if possible. Sweet truck!! How long is your flat bed on yours?
That sounds like a pretty sweet idea! If you have the means I would say do it. My flatbed is 14’ long. Which is perfect really. The buggy is very long, the wheelbase is 126” so it fills the whole bed but 14’ makes for plenty of room.
Does that not have an exhaust brake? I know the feeling living in Colorado and being 80 foot long, we can’t avoid the passes. I have an exhaust brake, but have to go very slow to make it work well.
It does have an exhaust brake, which helps a lot but couldn’t hold me back on this road. I honestly has no business on this road. After pulling over for the brakes, I did pull it down in 2nd gear manually and keep it very slow and that helped a lot more.
I'm thinking an aux radiator and trans cooler, maybe under the truck along side of the drive line? About all you can do for the brakes is to NASCAR it, funnel air to the brakes with some fans to work even better at slow speeds. Does your truck have exhaust brakes?
Yeah the auxiliary radiator is up for consideration. However I just checked and I believe my fan clutch isn’t working like it should, again. So much Chinese junk on the market now. I don’t hear the fan at all, and it should have been screaming with it that hot. The brakes wouldn’t have been an issue if I had not been on and off, and not been on that road to begin with. I had no business on that road lol. It has an exhaust brake and it helps a ton. I’d have been in bad shape without it yesterday
Thanks for sharing tips. I'm thinking of trading up from 22 Duramax Dually to 5500. I heard the engine and transmission are very close to the same just de-tuned if that's right but stronger frame/suspension. Any advice?
It is the exact same drive train as a pickup, just in a beefier chassis. If I could spend the money I would get a semi converted to do what I need to do. Or I would have a Cab & Chassis Ram 4500 or 5500 with a 14’ flatbed. I believe I’m simply asking too much of this truck. But I’m also questioning of my fan clutch is failing again cause I did not hear the fan during all of this.
@@TaltonOffroadTravel So I'm looking to move from my 22 L5P dually to a Chevy 5500 with 24ft bed, however some guys say to get Ram 5500 then a few saying just save myself the pain by trading up into M2 106 Crew cab, so many darn paths and not knowing which engine/trans to better doesn't help me. I love your setup but I'm not sure if I trade up into Chevy 5500 if will last running 10k miles a month thanks for the advice
@@tg9388 if you’re towing heavy 10k per month I would skip an MDT and move right to an HDT. Unless you’re just burning up the interstate on a regular route, not really pulling crazy hills all the time. If that’s the case a Ram would do you good.
@@TaltonOffroadTravel Rv transport so Goshen, IN to WA/OR/ID each week some CA/AZ loads but all interstate for the most part. So your saying the 2023/24 RAM 5500 C&C 120" CA would be better than Chevy 5500/6500 ?
@@tg9388 personally I do. I’m a Chevy guy, all my chevys have had tons of miles. My previous pickup had 545k on it when I sold it, and my current pickup that my dad is holding while I travel has 430k on the original motor & trans. However with my personal preference aside, the torque that the 6.7 Cummins makes along with being reliable and easy to service and repair is hard to deny. The 6.7 comes in so many fleet and commercial applications that parts are plentiful. The 6.7 ford honestly pulls even better, but have you looked under the hood of one of those trucks? Lol. There’s no room to do anything. Repairs and stuff cost more. I’m not a Cummins fan boy, in fact I hate the way they sound and stuff but I can’t deny how well they do what they’re designed to do. I don’t know much at all about the newer Duramax engines though to be fair.
I have a quick question for yall.. I am looking at an 07 top kick 5500 2WD Duramax, 289,000 on her, We would be towing a 17000 dry weight 45 ft toy hauler, Do yall think this truck would be adequate? Oh it is a 4 door as well, they are asking 17,000.00 Thanks ahead o time!! Great video but intense!! L.T. Dan
At that price, if it’s in good shape then yes! Just know that it also cost that much to replace the engine 😖 However for a paid for truck, you can’t beat the brakes and suspension. Just don’t be in a hurry and you’ll be fine.
I can't believe there are still (so called) car people that haul close to and over max gross that don't have the BIGGEST possible alloy radiator, trans cooler, added electric fan switched to come on 20° before max temp. That should be done before a hitch install especially if it's not a brand new truck......can anyone say Fan Shroud.
I have all of these things. I'm not sure you comprehend the grade I was on in this video. Anyone who does not have a fan shroud and aux trans cooler should not be towing more than a lawn mower lol.
At that time, I had overheating issues I was battling among other issues. Didn’t help that I was on a scenic parkway road 🤣 Since this video, the truck blew up and left us in Arkansas but is all fixed up and running great now 💪
Your brakes should be fine by the way cuz once you got them cooled off he started moving the biggest thing is you don't want to let breaks it and stay hot you probably just took a little life out of them LOL but they should be just fine
Yeah everything seems fine. I am replacing the fan clutch before leaving here, as it is now spinning pretty free and I don’t recall hearing the fan for a while now and that may be my issue. If getting hot still happens I will be looking at external oil and trans coolers
Duramax. A bit underpowered considering the load but it works well. I’m in AZ now and just put in a new all aluminum radiator. Hopefully good to go now!
@@TaltonOffroadTravel I would take the duramax over the 3126 cat like I have. Terrible mileage and can’t get out of its own way. New crate motor and it’s back to cat because it uses 1.5 gals of oil every 1000 miles.
Your way to heavy for what that truck is rated for. No exhaust brake ? Your lucky you didn’t get caught on the byway. Too heavy and too long your in the zone where the truck and trailer fall under commercial vehicle limits !
Yes, very lucky indeed. Also, yes, a bit too heavy for the truck but kinda stuck now lol. It does have an exhaust brake. I’d have been in bad shape without it
Hi whatcha up to hope all is well prayers 4 healing and unspoken also prayers 4 everyone and bless great healthy peaceful safe journeys and travels in the name of the Creator God and Yeshua/Jesus and the Holy Ghost Amen much honor and respect keep walking tall yall also transmission cooler and oil cool is needed if u don't have them if u r going do much mountain driving also jake brake would help too many blessings keep walking tall and keep on keeping on many blessings cool cool set up 🚌🌅🌌⛺🌄🏞🏖 👍👍💪🙂👍👍
U think bama roads r bad go to TEXAS. There the interstates r horrendous, especially I 35. Take out any dentures or partials, if u don't they'll be in pieces.
Ahh, my first negative comment. I knew it would come eventually. Thanks. FYI the transmission was just fine and never overheated. But thanks for taking the time to leave a negative comment
