high rpms??

southerndog · 08-22-2008, 06:25 PM

2002 Adventurer 32V with ford v-10, does 2500 to 2700 rpms at 60 mph seem to high? flat road,,no hills.

southerndog · 08-22-2008, 06:25 PM

2002 Adventurer 32V with ford v-10, does 2500 to 2700 rpms at 60 mph seem to high? flat road,,no hills.

smlranger · 08-23-2008, 02:49 AM

Since your question is more related to the Ford chassis/engine, I have short-cut your post to the Ford Chassis Owners forum.

FYI, I have owned Ford trucks and SUV's all my life and every one I've had turned about 2000 - 2100 rpm's at 65 mph...most I've owned had either the 3.73 or 3.55 axle. 2500 - 2700 sounds a bit high at cruising speed...are you sure it is going into overdrive or do you have overdrive locked out?

John Hilley · 08-23-2008, 04:19 AM

That is what mine does also. I drive 55 at about 2300 rpm.

Hikerdogs · 08-23-2008, 04:19 AM

The engine rpm's of 2500 - 2700 for 60 mph is normal for your year. It's exactly the same as our 01 F53 chassis. We have over 65,000 miles on our coach without any engine problems. We average 8 mpg without a toad (on regular gas with no ethanol), and a little over 7 mpg with a toad (04 Jeep rangler). Keep in mind the differential gear ratio is much higher than on a car or light truck at 5.38/1

Izzyblueye · 08-24-2008, 05:47 AM

my F-53 runs 2000 rpm's at 60 mph in overdrive. My brothers F-53 does exactly the same rpm at that speed.

NeilV · 08-25-2008, 12:28 AM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by southerndog:
2002 Adventurer 32V with ford v-10, does 2500 to 2700 rpms at 60 mph seem to high? flat road,,no hills. </div></BLOCKQUOTE>

Yes it does. That is what I get when I depress the button on the end of the shift lever and acidently shut out the overdrive. If the light in the end of the shift lever is lit then overdrive is turned off. You may want to test the overdive buttons operation and see if the rpms go up or down. It could be that the indicator light is burned out.

Hurricaner · 08-25-2008, 09:24 AM

I'm not sure where some people are getting there info but this is directly from Ford.

F-53 Motorhome Chassis 2000 Model Year and Later - VEHICLE SPEED (MPH) COMPARED TO ENGINE SPEED (RPM)

MPH-----GEAR-----RPM

______1st
05_____=_____900
10_____=_____1600
15_____=_____2450
20*___ _=_____3250
25_____=_____3970
30_____=_____4800

______2nd
20_____=_____1880
25_____=_____2290
30_____=_____2830
35*___ _=_____3260
40_____=_____3600
45_____=_____4130
50_____=_____4500

______3rd
30_____=_____1710
35_____=_____2050
40_____=_____2350
45_____=_____2600
50_____=_____2900
55_____=_____3170
57*___ _=_____3250
60_____=_____3460

____Overdrive
40_____=_____1630
45_____=_____1850
50_____=_____2050
55_____=_____2270
60_____=_____2450
65_____=_____2660
70_____=_____2850

Note: * Maximum Engine Torque (3250 RPM) occurs at MPH Indicated
Max. Engine Speed = 5260 RPM (Approximate)
Max. Vehicle Speed = 83 MPH (Approximate)
75 MPH (2004)

Sam

Izzyblueye · 08-25-2008, 10:15 AM

HURRICANER: The next time I take my coach out on the road I will try to photograph the speedometer and Tach at exactly 60 mph. It will show 2 grand on the Tach in overdrive. Remember when Ford brought this chassis out they said 7 qts of oil too, NOT. Didn't even get the right dipstick for the new engine.

Hikerdogs · 08-25-2008, 12:44 PM

When others mentioned they thought the rpm's were too high I did the math.

With the engine @ 2,500 rpm and the transmission in OD the tailshaft will spin @ 3521 rpm (gear ratio .71/1).

With a 5.38/1 differential the axle should be spinning @ 654.5 rpm.

If the tires are the same size as ours (245R70/19.5) they will be 33" in diameter and be covering 5654.8 feet per minute.

That's slightly over 60 mph, so if the engine is running at approx. 2500 rpm all is well.

On Edit: I originally said "That's slightly over 60 mpg" not 60 mph (I would love to see 60 mpg, but I doubt it will be in our current coach)

John Hilley · 08-25-2008, 01:02 PM

Mine matches the chart.

tderonne · 08-25-2008, 01:13 PM

What Hikerdogs said....

The 245/70R19.5 tire turns 627 revolutions per mile according to Goodyear. At 60 MPH the tires will be going 627 RPM. 627*5.38*.72 (I have .72 as the ratio for OD) = 2429

Folks with 22.5" wheels will show about 11% less RPM. Not sure what the 225/??R19.5 tire size will do...

southerndog · 08-25-2008, 02:28 PM

Thanks for the info,,,didn't mean to open up a can of worms. LOL

LVJ58 · 08-25-2008, 02:35 PM

Remember when Ford brought this chassis out they said 7 qts of oil too, NOT.

Hmmm, the owner's manual on our 2000 listed the oil capacity as 6 qts.

Must have been a typo in yours.

Izzyblueye · 08-25-2008, 03:51 PM

FORD: didn't say 7 quarts, but 6 quarts did not take it to the full mark on the dipstick. It took seven to reach full. Mis calibrated dipstick for the engine. The local Ford dealer confirmed it took 7 quarts, he was misinformed also.

NeilV · 08-26-2008, 01:13 AM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by southerndog:
Thanks for the info,,,didn't mean to open up a can of worms. LOL </div></BLOCKQUOTE>

No can of worms here so don't worry about it.

Your tires could be a bit worn while mine are new. I am seeing only around 2300 rpm at 60. I am going by a digital tachometer off the OBDII port and not the dash unit.

Tire wear, tire pressure, road conditions and transmission slippage all will have an effect on your rpm for a given speed.

2700 rpm puts you at over 65 mph by the book however consider the other part of the equation, how accurate is your speedometer and tach. If you have a GPS unit available how does the 60 mph of the speedometer compare to it? Mine is close to an exact match when holding a steady speed just slightly over with the new tires while it was slightly under just before I changed them.