safe rpm range?

[broncobuyer]

what is a safe rpm range for an idi on a long haul towing? my 89 f250 has a zf 5 spd 235/85/16 tires and at 65 mph it revs 2600 rpm, at 75mph it revs 3000 rpm and at 83 mph its hitting 3400 rpm which is in the yellow, im assuming i have 4.10 gears because of the high rpms, what would be a safe cruising rpm when towing with these trucks?

 

[rhkcommander]

governor as long as your not hitting egts too high, especially with uhaul IPs governed to ~2850

 

[rjjp]

3000RPM at 75mph with a 31.7" tall tire (235/85/R16 is numerically 31.7") with .77 OD (some ZFs are .78 some are .76) figures out to roughly 4.90 rear gears.

 

[itsacrazyasian]

For the past two weeks i've been making a 5 hr trip each way down to the Keys. running against the governer every time and other than sucking down alot of fuel, the motor don't care.

 

[Dieselcrawler]

safe rpm? that would be 0 to 3400 rpm. anything in that range is safe.

 

['94IDITurbo7.3]

for me 70 mph runs about 2400-2500 rpm.

either your speedo is off or your gearing is not 4.10

 

[towcat]

listen to your truck. It will tell you if it's ok or not. All my F450's have numerically high ratios and there is no choice other than to run pinned against the governor. My carrier has enough fuel capacity to run for 10 hours pinned and still have plenty of fuel left over. My bladder otoh thinks differently. Four hours pinned was enough in the summer. As long as you are throwing a load against the motor, it's all good.

 

[dyoung14]

If i wanted my engine to last forever i would stay at 3800 or below, running on the govenor will hurt nothing but your pocket when you fuel up. now everyone here is going to tell you that exceeding the governor will blow your engine, well here is my 2 cents i ran mine to 4500 many times that motor is setting in a garage right now waiting to find a truck body to place it in, still runs fine, my new motor is about to get a 4500 spring. i dont recomend anyone do this unless your crazy like me

 

[jwalterus]

safe rpm? that would be 0 to 3400 rpm. anything in that range is safe.

I seem to be having problems any time I'm running loaded and my rpm goes to 0.....

 

['94IDITurbo7.3]

I seem to be having problems any time I'm running loaded and my rpm goes to 0.....

that would be a bad day.

does running these truck near 2300-2500 rpm on the e-way REALLY tear into mpg enough to warrant taking back roads?

 

[redneckaggie]

If taking back roads warrants stopping and starting because of stop signs and such then those will not increase milage. they probably would decrease milage and also increase maintenence costs because of using the brakes and trans wear and such. best equation to increase milage is to stay on open roads and keep the rpms down, but not to the point of bogging. the right lane is your friend and others can kiss my ass

 

[hesutton]

what is a safe rpm range for an idi on a long haul towing? my 89 f250 has a zf 5 spd 235/85/16 tires and at 65 mph it revs 2600 rpm, at 75mph it revs 3000 rpm and at 83 mph its hitting 3400 rpm which is in the yellow, im assuming i have 4.10 gears because of the high rpms, what would be a safe cruising rpm when towing with these trucks?

RPM ......... Your engine will tell you where it is most comfortable pulling a load. My 6.9 likes 2500 +/- when pulling the camper, regardless of the road speed. The other thing.........there is a bit of difference between safe RPM and safe road speed. Dude, you aren't hauling heavy loads at 83 mph right?

Heath

 

[freebird01]

W/ 3.54 axle gears and a ZF5 speed and 285's running empty mine liked around 2200-2300 for cruising 65-70 and 2500-2600 when towing

 

[rjjp]

RPM ......... Your engine will tell you where it is most comfortable pulling a load. My 6.9 likes 2500 +/- when pulling the camper, regardless of the road speed. The other thing.........there is a bit of difference between safe RPM and safe road speed. Dude, you aren't hauling heavy loads at 83 mph right?

Heath

Depends, you a LEO?

 

[hesutton]

Depends, you a LEO?

Nope, not me. But, I don't like being on the same road as dudes that haul that way. If someone injures me or my family hauling like that, an LEO may find said person head shot at the scene though.

Heath