how do i know if o/d is working or not?

[LiKuiD]

im pretty sure while driving on a trip today the tranny only shifts 3 times and when going about 75mph my engine is at 2800-3000 rpm. this sounds high and after reading alot im guessing im not shifting in to o/d...i have a first generation X so i dont have the button. could this be a sign of a going tranny? ive never had a problem w/ this truck at all...runs perfect and just hit 73k miles. any ideas whast goin on? thanks alot

 

[Robb]

I think I usually run about 3K rpm at 75-80mph. I believe this is about normal. I would be interested in replies that say it isn't.

 

['96explorereddiebauer]

It really depends on what your gear ratio is. Mine is 4.10 and it's about 3200 rpm at 70-75mph.

 

[B94Sport]

I'm not sure what my gear ratio is (I really should figure that out...) but I run at exactly 2500 RPM at 75 MPH.

 

[Texan01]

if it shifts 3 times then it's going into overdrive. otherwise it'd only shift twice.

Mine runs 2200-2500 rpm at 75 and it's got a 3.73 it OD off and it'll run at 3300-3500.

 

[ajevenson]

mine runs 2000 at 70mi/h and 2300 at 75mi/h. I find that I can't climb hills or pass anyone unless I am goin at least 75mi/h.

 

[LiKuiD]

yea you guys are right. i cant count! the o/d works fine. thanks alot!

 

[VairKing]

What is a safe operating range w/o od? mine went out, and i usually set the cruise at 75mph@3500rpms...Is this safe???

 

[JDraper]

It's completely safe.....just lousy on fuel mileage.

 

[Jason_25]

Originally posted by VairKing
What is a safe operating range w/o od? mine went out, and i usually set the cruise at 75mph@3500rpms...Is this safe???

Man that has to be noisy.

 

['96explorereddiebauer]

It's not that noisy. I set the cruise at 75mph@3200rpm and it's pretty quiet (that's with the O/D engaged). Since I do a lot of highway driving, it'd be better if I had a 3.73 rear-end instead of 4.10 rear-end but hey, I'm not complaining.

 

[Hartman]

Is it weird that I only run about 2500 RPM's at 75 with the OD on?

 

[Alec]

I run somewhere about there Hartman, it's perfectly fine; good gears for highway mileage.

 

[VairKing]

Wheew, I feel better now...I usually get about 15-17 mpg on the highway...Too bad im too cheap to put a $1300 tranny into a $3000 truck...

 

[2001ExpSport]

RPM ranges can be fairly wide. Depends on gearing, transmission and tires. I cruise 75 at right about 2 grand, but i have the 5R55E auto tranny(5 speed w/OD). A good way to tell if it is in OD is to lightly press the gas to accellerate. If the RPMs stay were they are and don't rise then it is in OD. OD is basically the converter locking up. If it is not in OD when you press the gas the rpm's will rise a few hundred rpms as soon as you press it.