I just came back from a 2500 mile camping trip. I was climbing some nasty hills with up to a 50 mph headwind. I was at 12000 pound gross with the cruise control set at 70 mph. When vehicle lost power down to 60 mph, the transmission would not downshift and the cruise shut itself off. At 62 mph, the transmission would downshift at 60 mph. Is this normal?

I set the cruise at 75 mph once I got on the Interstate and this thing blew by every RV'er out there. The winds kept everyone under 65 mph. This 350 mile stretch cost me 7.5 mpg verses 10.5 mpg at 62 mph.

03 F350, cc, V10, auto, 4X4, 3.73

 

Tons of differing opinions here on towing with out cruise on or off.

I personnaly recommend towing heavy loads up hills to just turn it off and get the engine up to 3800-4000RPM where it LOVES to pull... Others totally dissagree and are usually motivated by trying to get the BEST fuel milage... just opinions and we both are right.

The kicking cruise OFF condition I have not seen, but unless it consistently miss behaves I wouldn't worry about it. These electronic things are finicky sometimes.

Noted that most of us have a cruise control surging problem at 68-72 mph (not every truck does it but a lot do)

Sounds like, at your weight and the head wind, you have a good truck with plenty of power.

Is it normal?.....who knows too many variables, but I suspect that it was just doing it's thing for the grade, weight, throttle position , and torque load.... some owners are mildly concerned over the quirky behavior others are super parinoid about it.

Remember that the 4R100 has and "adaptive" learning module in the PCM and this has a lot to do with the behavior of the torque converter and shift pressures and shift points. (if it learned your habits with OUT a load, and only around town, then under load out on the road, it will behave strange for the conditions)

Additionally the tranny fluid needs to be kept under 230F as near this temp the fluid turns from a lubricant to a scorched oxidized mess that will not shift correctly, cause greater wear and continue to increase heat buildup. (this is a drum I beat loud and often)

 

Thanks. It just freaked me out the first time it happened.

Another worry I had was pulling for 350 miles at 3000 rpm and some steep grades at 4000-4300 rpm. I had no idea what redline is but I thought the max hp is at 3750 rpm so I really was not to concerned.

I am not use to the automatic and I had a few choice words for it at times. Actually, I cursed the other automatic that I once owned so it is just a personal preference.

 

Trust me brother, that V10 LOVES 3800-4500 RPM and will do it ALL day long... unsettling for many because it sounds louder

and of course it sucks fuel like it was 1972 and $0.27 per gal


On the other hand my old F250 4X4 460CI was not as heavy and sucked much more fuel. Can you imagine getting 5mpg today?

The PCM keeps the MPH at or below 95 and the RPM should be limited to 5000 +/- 200

The engine is designed to take 6000 RPM so the rev limiter is conservetivly set

 

Fredvon is right. When I'm pulling 11000 GCW, up the west side of the Eisenhower tunnel approach, I lock in 2nd, run it up to 3900-4200 rpm = 55 mph, at 10, 500 ft.. I can almost hear the fuel tank collapsing.

 

i could be wrong here but i believe the max hp on a v-10 is @ 4250 rpm instead of 3750.

 

max torque @3250 rpm
max hp @4250 rpm

If max hp is at 4250 then I assume that I can run at this rpm all day long.

 

Hi, I'm new to this list. I was driving a couple weeks ago on IH10 in Texas. There were a few hills, and on a couple of them, I could not keep the truck over 60 mph. I was only towing a 2500lb camper. After reading some of the previous posts, I could have just downshifted and got up to 4000rpm. I tried this today and there is a LOT more power. Is it safe to drive continually at 4000rpm without hurting the engine or 5-speed tranny? What is the red line?? Also I had the A/C on. Usually I don't have a problem without the A/C.

'99 F250 V10 4x4

 

I pull a 8500lbs 5th'er out of Vegas all the time to Arizona and Utah and have no problem on the hills and the speed. Do not have any concerns about the rev's @ 3800-4000. These veterans on this site are absolutley right, these V10's love to pull at that mark and will pull anything ALL DAY long. Watch your temp on your tranmission and keep your foot on the gas. Personally I find that it is more comforting to throttle the down shifts instead of keeping the cruise control on up the steep grades.

I have never, ever had a Chebby pass me up. It just keeps giving me those BSEG's.

(BIG ***** Eating Grins)

Vegas
(I love these trucks!!)

 

FYI, Fredvon4, there is a fix for the CC surging at 68-72. It's the ABS module that needs to be replaced.

 

utilitypigeons

Welcome to FTE!!!

This thread answers you speed all day question but I will add the other answers. 5speed manual should not have any problems at higher RPMs. But if your 99 has the 4R100 there was a TSB to change the trans cooler as the factory initial method did not work properly under load.

Ford SuperDuty series with the 4R100 trans only have ONE real fault. Transmission Adaptive Learning module in the PCM (Power Control Module) the computer.

Stock the "Red Line" is never realised because the facrory set the rev (RPM) limiter to 5000 (+/- 200) they also set the MPH limit to 95 (+/- 3).

The design of the modular V10 will allow 6000RPM upper limit before ugly things happen (most notably the valves will float and ignition dwell time is too short for a good spark to be developed)

I had not heard of the cruise surge being fixed. What forum was the thread on?

 

I can't tell you how gratifying it was to be able to pull those grades on the !-15 between San Bernardino, CA and Cedar City, Utah with the speedo sitting mostly at 60 or 65, while towing a 30-footer TT, with all the stuff mama could pack into it.

I was amazed at the rpm's this V-10 can run at, thanks to no push rods or lifters. My 460 could flatten lifters at 55 mph, and that's with a 3.55 axle compared to the V-10 in front of a 4.10 axle.

My only complaint had nothing to do with the engine. It was the radiator that let me down. (Well, it did have 168k miles on it, so it wasn't like it was a new one).

I was not paying attention to my speed with the cruise control on as I entered a grade 26 miles west of Mesquite, Nevada. Before I knew it it went from O/D to 3rd (1:1), then just as quickly to 2nd gear. Okay for the engine, bad for the tired out radiator. The plastic tank split spewing coolant all over the place.

Thankfully there was a good shoulder in that little pass, and I headed right onto to it and shut her down.

$543 for the repairs, and $150.00 for the tow, I was on my way three days later.

I LOVE that V-10!!!!!!!!!!!!!!!!!!!

 

I'm not sure forum that was in. I know it was under a cruise control topic.

I had mine fixed about 6 mo ago.

I'll see if I can find it.

 

Fredvon4 & Vegas V10
Thanks for the help,
How do I find out what kind of transmission I have?

Jason

 

Didn't know that! My 2001 F-250 intermittently surges around 70 MPH... Obviously a dealer fix if still under warranty.

Edmo