3.5 Cruising RPM

[magoh76]

Hey guys (and gals, don't wanna discriminate), quick question hopefully. What kinda revs should I be expecting when cruising my stock 2001 XLS at 65 MPH down the highway? Does 3000 rpm sound right? I searched all over but couldn't find this discussed elsewhere.

Thanks!

 

[grandpa]

That sounds a little high. What size tire do you have?

 

[magoh76]

265/70 R16

 

[Toasty]

sounds about right if your truck came with 4.90 Axle ratios (A lot of Sports came this way stock), otherwise maybe your over drive is not engaging. 3000RPM is nothing these motors can't handle don't worry too much. Or buy bigger tires.

 

[Inyo_man]

I'm running 265/75/16's without adjusting the speedo.
At 65 mph on flat road, the tach. reads spot on 2400 rpm.
3000 sounds a bit high. What's the rpm of your rig at idle?

 

[magoh76]

A couple of days after I started this thread the engine started staying at ~2700 rpm at 65. Not sure why it was higher before. Idle is a hair below 1000 rpm. I do have some engine codes I had read the other day, relating to the o2 sensors and cat, and also looks like I need to replace thermostat or temp sensor.

 

[Mrknowitall]

3000rpm might be right is the converter isn't locking up. In theory, it should be just over 2600rpm (see below). If all is well, deviation can come from the spedometer, but shouldn't be more than 5% or so. The Limited will turn 2300, since it has 4.30 gears and the same OD.

Per tire rack, the OE tire has 676 rev/mile.
X 4.90 axle ratio
X 0.73 Overdrive.
X 65 mph
/ 60 min/hour
----------------
2620 rpm

 

[off-roader]

Hey guys (and gals, don't wanna discriminate), quick question hopefully. What kinda revs should I be expecting when cruising my stock 2001 XLS at 65 MPH down the highway? Does 3000 rpm sound right? I searched all over but couldn't find this discussed elsewhere.

Thanks!

FWIW, I just checked my rpm this evening & at 65mph I'm at ~2500rpm with my 33" BFGoodrich AT tires.

 

[magoh76]

So it sounds like 2700 isn't too far off since I have the XLS, and when it's running higher it's because of the catalytic converter not working right?

Thanks for all the input!