driving rpms

[iceman2114]

what should the cruising rpm beat 55 mph has a 2.9 v6, a4ld, driving in just 2wd, right now im sitting at about 2700rpms, and was thinking it seemed a little bit high, and how would i be able to change this?

 

[tanbuddy]

what size tires and rear axle ratio do u have? Im at 2000 at 55

 

[RustedRanger]

I dont know my axle ratio but I got 225/70/15's and the door says it came 205's. I turn about 21-2200 at 55 with a 5 speed. 2700 does sound kinda high. Makes me wonder if your torque convertor is locking up when it should. You could put on taller tires to lower the rpms but it will be harder on the transmission.

 

[Tedybear]

Perspective.

I've got my BII (in sig) and it has oversized wheels and 235 x 15 tires on it. (it can support 255 or more...dang wheels are about 11" or so wide)

Doing 55 in overdrive it pulls about 2100 give or take a bit. At 65? Normally (and this is the odd ball part) 2500 when warmed up and run in a bit. 2750 when stone cold first thing in the morning. (It's always been that way sense I've owned it, might be a wonky tach when it's stone cold?)

When the truck/suv hits about 45mph under mild or holding it steady for the accel? You can feel the overdrive/TCC kick in. It will be about 3000-3100 rpm...and then DROP like a rock about 600 RPM.

Normally you can check the harness going to the transmission to see if the plugs are loose/buggered up...The computer sends the signal...and the solenoids do the rest.

S-

 

[RavoHimself]

sounds like you need some bigger tires

 

[iceman2114]

i have 235/75/15s, the rear end is all stock. would i get any codes for the torque converter being bad?

 

[dernst]

My truck runs about 2700 RPMs in 4th and about 2100 RPMs in 5th while driving 55 MPH. It has 3.73:1 gears and 235/75 R15 tires with a manual trans. If I am driving at 55, I wouldn't even put it in 5th gear. I like to keep the rpms between 2500 and 2800 when I am cuising along. It sound like most people like to lug their motors. You will get the best gas mileage if you operated the motor around peak torque which is at 2600 rpms.

 

[RustedRanger]

I don't know if the torque con would leave a code or not if bad,mine is a 5 speed. In other vehicles I have just shifted manually so I could clearly feel each gear and after its in OD watch to see if the rpms drop a little more.

 

[mhughes165]

My truck runs about 2700 RPMs in 4th and about 2100 RPMs in 5th while driving 55 MPH. It has 3.73:1 gears and 235/75 R15 tires with a manual trans. If I am driving at 55, I wouldn't even put it in 5th gear. I like to keep the rpms between 2500 and 2800 when I am cuising along. It sound like most people like to lug their motors. You will get the best gas mileage if you operated the motor around peak torque which is at 2600 rpms.

yes, for some reason some people feel the need to have there RPMS as low as possible, when in reality u can get worse mileage, when ur in the happy place its the most effiecient

 

[RatDog8o8]

Just got my '92 4x4 on New Year's Day. It's an automatic, with 4.10 gears. Around town, it "hunts" when in OD. Running 235/75R15's on stock rims. Should I drop it out of OD in town? Haven't tried it on the highway yet to see what the RPMs are at speed.