floorboards hot on long trip

[babycampers]

We just traveled 2300 miles (first long trip) towing our NC 29FKS (appr. 12,000 lbs) w/'99 7.3 SD stock. It seemed like the floorboards and firewall were extremely hot all the time but temp. gauge never got high, nor did the truck seem like it was having any other problems. Ambient temps were 80s/90s most everywhere but I don't think that would cause the degree of heat we experienced. Am I being neurotic about this heat thing, or is our new "3 exhaust a big contributor to all the heat? I've read a lot on this forum about the necessity of the bigger exhausts and air filter upgrades when towing. We also noticed that just going over 65 mph really jacked up the RPMs. Do most of you run about 65 regardless of the 70 speed limit areas?

 

[tmcran]

Humm, how did you realize they were getting hot? Could feel the heat in your feet,legs and etc? I believe the RV tires are rated for 65 MPH. I don't driver faster then 65. Helps my mileage and I feel that is fast enough. Got lots of informed folks and I bet someone will have an answer.

 

[RollingHome]

Babycampers, maybe I'm just turning into an ole fart but... I keep it under 60 mph and it really doesn't take that much longer. It's also a lot more relaxing and enjoyable. Try doing the next trip under sixty and keep telling yourself. I'm not in a hurry, I'll get there 15 minutes later then I want to and that's OK... Seriously, give it a try, you just might enjoy it and live longer... Keep in mind, this sage advice is coming from a guy who also does a couple of hundred miles an hour just a few feet off the ground... Don't ask

 

[Bob&Patty]

Here's my 2ct's. Did you say a bigger exhaust pipe?? Has your engine been juiced?? Several points to ponder.

Chips dump more fuel. More fuel ...more heat.
Bigger exhaust...closer to the floor board.
Pulling a RV of any kind makes things work harder....more heat.
Transmission temps will rise pulling....more heat.
Pulling at higher speeds....takes more energy....more heat.


I think you see where im going. Your fuel mileage will be better at lower speeds. Easier on your TV, tires and your wallet. As to your question. I run a 62MPH and 1650RPM. If you run at 65 MPH for 1 hour and I run at 62MPH, you with be 3 miles ahead of me in 1 hour. Somewhere about 17K feet. If you stop, it will take me 3 minutes to be where you stop. I'm getting 12 MPG and what are you getting at 65-70 MPH.

 

[caissiel]

When I towed with my 98 GM Diesel the passenger side floor got hot. It was a normal thing with the 98.
Exhaust on the older trucks don't have the free flow the newer trucks have.

An Exhaust Temp Gauge would indicate your temperature and you could then drive with a cooler exhaust.

My 98 was not so great on fuel but it was better at speeds over 65MPH. I think it was due to lack of power and the torque curve.

The F250 has to be keeped under 2000 RPM so I just drive at 55/63 at 1700/1900 RPM. for best millage.

 

[SouthernNights]

We just traveled 2300 miles (first long trip) towing our NC 29FKS (appr. 12,000 lbs) w/'99 7.3 SD stock. It seemed like the floorboards and firewall were extremely hot all the time but temp. gauge never got high, nor did the truck seem like it was having any other problems. Ambient temps were 80s/90s most everywhere but I don't think that would cause the degree of heat we experienced. Am I being neurotic about this heat thing, or is our new "3 exhaust a big contributor to all the heat? I've read a lot on this forum about the necessity of the bigger exhausts and air filter upgrades when towing. We also noticed that just going over 65 mph really jacked up the RPMs. Do most of you run about 65 regardless of the 70 speed limit areas?

I have a few questions.

1)You said the that temp of the floor board SEEMED high. Is this just a feeling or did you actually shoot the floor boards with an infared checker?

2)Did you just have a new 3" exhaust installed? If so, is that the stock size for your engine? Is it run excatly where the stock system was? or is it an aftermarket system-maybe closer to the firewall and floorboards?

3) As far as the "necessity of aftermarket intake and exhausts"-YES they can cause more heat for the very reason Bob mentioned. And they are not necessary. Of course everyone has an opinion about that. But think of it this way-If all these aftermarket things actually helped fuel mileage, horsepower, tourqe, durability and longevity - dont you think the manufacturer would be doing it straight from the factory? Some aftermarket products help in one or two areas but for a total package I dont understand why people try to outguess the engineers.

4) As far as running 65 or 70-I typically keep it at 65 for no other reason than fuel mileage. Somtimes 70 if traffic dictates but not very often and usually just to get around another vehicle.

 

[scotty]

We just traveled 2300 miles (first long trip) towing our NC 29FKS (appr. 12,000 lbs) w/'99 7.3 SD stock. It seemed like the floorboards and firewall were extremely hot all the time but temp. gauge never got high, nor did the truck seem like it was having any other problems. Ambient temps were 80s/90s most everywhere but I don't think that would cause the degree of heat we experienced. Am I being neurotic about this heat thing, or is our new "3 exhaust a big contributor to all the heat? I've read a lot on this forum about the necessity of the bigger exhausts and air filter upgrades when towing. We also noticed that just going over 65 mph really jacked up the RPMs. Do most of you run about 65 regardless of the 70 speed limit areas?

Don't know if you've been there, but go to dieselstop.com. This is or used to be the Ford diesel site, haven't been there in a couple of years. Anyway, I had a 2000 7.3 (best truck I ever owned) and there is a wealth of info on there. Never had a problem with what you're experiencing, but you can get answers there on all Ford issues, great site. If not already suggest you at least get an EGT gauge to keep an eye on those exhaust gas temps when towing. the 7.3 turbos don't like it above 1300 F for long.

 

[Bob&Patty]

Scotty, boy you are right on the money with the 1300* statement. Even big ol' truck engine dont like anything over that. Melting the pistons in one of our little trucks is very costly. But a 1000 Ci Cummins or Cat...........you would need a dump truck to get all the parts off the road.

Larry, you are spot on about all the aftermarket stuff. I talk to our Duramax techs at our dealer all the time. They all said its a waste of money. I have never intended to "juice" my OL' smokey. I get good fuel mileage just the way it is. It's not a hot rod...I bought it to pull..not drag race. I still am waiting for someone smarter than me to explain how dumping more fuel in a diesel engine will get better fuel mileage. The more fuel you dump...the more fuel you use. The more fuel you dump.... the hotter the cylinder temps are. What am I missing here. I guess being a GM tech for 46 years..I must have missed something in basic engine design and operation.

 

[traveler44]

We have a stock 2000 7.3 psd and our floor boards and feet get plenty warm too. We turn the a/c to the first click to the right where it shows feet and dash and ours is bearable that way. I am willing to sacrifice a little fuel milage for the extra comfort. I am going to look into a EGT gauge and have a trans. temp gauge that I installed last fall. We pull a 5th whl. that weighs about the same as your unit and it pulls real good at about 62mph. I plan on getting one of those infrared heat indicating guns just to keep an eye on tires, wheel bearings, and to make sure that the brakes don't drag. 2300 miles sounds like a good trip I'll bet it was fun. Tom and Mary

 

[RollingHome]

Traveler44 and others, You may want to investigate some of the electronic monitors (gauges) out today which plug into your data port under your dash. These give anywhere from 20 to 120 different outputs. i.e. trans temp, EGT, oil pressure, engine temp, turbo temp, etc. etc. They cost a couple of hundred bucks and fit into a housing on your A-Pillar (windshield post). They gather data from the computer. The more complex units require additional transducers and gizmos. Some even allow you to reprogram the eProm to "chip" your engine on the go. They go from A simple to Z complex. Auto Zone even sells em. Instead of texting while you drive you can commit "data acquisition" while you sing nearer to thy. Just a thought. Tom

 

[Bob&Patty]

Tom, "Nearer my God to Thee" the band sang as the Titanic sank. Are you trying to tell us something???? I guarantee The Horn or Chebby won't float very long.

 

[babycampers]

Humm, how did you realize they were getting hot? Could feel the heat in your feet,legs and etc? I believe the RV tires are rated for 65 MPH. I don't driver faster then 65. Helps my mileage and I feel that is fast enough. Got lots of informed folks and I bet someone will have an answer.

Yes, most of the time I could barely tolerate leaving my feet on the floor, not to mention that my dogs couldn't even take lying on the floorboards (which is uncommon). We didn't believe we could justify running the A/C and burning even more fuel on such a long, expensive trip. You know how affordable diesel is these past few months!

 

[babycampers]

I see by the numbers of replies that most of you do stay around 60 or so. Wonder how come so many other RVers were passing us up then?! They must be getting their fuel free! LOL

 

[babycampers]

#1. It felt much, much hotter than any other trips taken on 90 degree days - I have never had to keep my feet off the floor like this trip. No, I didn't have a gauge, but wished I had!
#2. 3" was the prior exhaust system size so we are assuming that if it was too small, our mechanic would have made us aware of that fact. I would hope my mechanic knows where it goes since he has the same truck for his towing company.