Are my "rpms" too high?

[1Byounkin]

I have a 1991 ford explorer 4x4 all standard. With an automatic transmission. I travel everyday in the highway which is 70 mph. I mostly go 65 mph and my rpms stay at 3,000 rpms if I stay at that speed. 55 mph is 2,500 rpms. Is this normal? Increase speed rpms increase. 70 mph 3,500 rpms. I think this high rpms is starting to make my truck use oil. Every gear hits and works great. Engine runs great, even has new plugs. I believe the air filter is clean. Could the fuel filter be dirty? But the engine runs great. Standard tire size ( 235 75 R15) Is it commend to run 3,000 rpms at 65 mph?



Thanks

 

[BrooklynBay]

Welcome to this forum! You should replace your transmission filter, and fluid, adjust the bands, and the kickdown cable. Is your modulator the adjustable or non adjustable style?

 

[1Byounkin]

I had the transmission rebuilt almost a year ago. But is adjusting the bands hard? Filter is easy. The modulator is non adjustable. The transmission place said they couldn't use the adjustable modulator because there is not enough adjustment for them to use that. I had to get the transmission rebuilt because the truck would not take off in over drive.

 

[rhauf]

assuming you're truck has stock gearing, it sounds possible that the truck isn't going into overdrive (or the torque converter isn't locking) i usually run approx 2500rpm at 70mph in my '93. so there's a reference for you.

high rpm won't make the truck use oil. remember old cars didn't even have an overdrive, and would normally run 3000+ rpm on the freeway, even with huge v8's.

 

[rhauf]

one other thought... is there any check engine light or codes that you know of? it's possible the electric connector for OD/ODlock isn't plugged into the trans...

 

[1Byounkin]

There is no codes. The truck hits ever gear. But it does act as it needs to go into one more gear. It will going the passing gear at that speed. Everything was replaced when the transmission was rebuilt a year ago. So if the "torque converter isn't locking" how can this be fixed?

 

[rhauf]

you're truck should shift through 5 "gears" from a standstill, to freeway cruising speed. it would go like this: 1'st, 2'nd, 3'rd, 4'th, 4'th lock. 4'th lock (or 5'th) is an electronic function of the transmission which bypasses the torque converter.. a way to test that it's locking up correctly, would be, while cruising at freeway speed, let you're foot off the gas pedal for a second, that will unlock the torque converter. when you put you're foot back to cruising position, it will appear as if it has downshifted, then it will "shift" back into lock-up mode... if that makes sense.

 

[1Aauto]

Welcome to the site.

 

[1Byounkin]

Thanks 1ATony.

rhauf - I know as I travel at 60mph (3000rpms) If you let off the engine speed will drop down to 2000rpms, than if to speed up there is nothing as in speed change until you hit 3000rpms. Even if you speed up pass that to 70mph you just speeding up the motor to 3200rpms. I think it should kick down. But it be rebuilt and its done this since is be rebuilt. I thought that it could because the down hardware needed to wear. So, what will be the best way to solve this issue?

 

[BrooklynBay]

The top of the transmission section has a sticky thread on adjusting the bands. I have the link in my list of useful threads. There is another link on adjusting the kickdown cable.

 

[1Byounkin]

That's cool. I guess I should take it to the transmission shop that rebuilt it since it's still under the warranty. Now I know what to ask for. It would be good to have them adjust it. If there were no warranty, then I would attack this problem myself.

 

[1Byounkin]

kickdown cable adjustment

The top of the transmission section has a sticky thread on adjusting the bands. I have the link in my list of useful threads. There is another link on adjusting the kickdown cable.

BrooklynBay- I did my own adjusting to the kickdown cable using 'zip-ties' at the gas petal. I saw the link you put on link on adjusting the kickdown cable: http://www.explorerforum.com/forums/showpost.php?p=2192755&postcount=11 I just need more info to adjust in the way you talk about. The truck does drive alot better kicking in great. I'll know more tonight how it will do on the highway.

Thanks

 

[BrooklynBay]

Take a look under the hood for the adjuster near the master cylinder. It has a part that you squeeze. Squeeze it, and pull at the same time. It will take up the slack of the cable going to the accelerator pedal. Pressing down on the accelerator pedal will automatically adjust the cable.

 

[1Byounkin]

Are you pulling the cable at the firewall? So after you squeeze and pull go inside the truck and push the petal to the floor. I have about 1" to 1.5" slack at the petal, with the spring.

 

[1Byounkin]

here is an idea of what my speed is now when cruising on the highway.

 

[BrooklynBay]

There should be a little slack on the cable after it's adjusted properly.

 

[1Byounkin]

so is mine adjusted right if it like I said 1" to 1.5". I know now if I move the petal the cable does not move. I can move the cable by hand. So what is the right adjustment slack?

 

[1Byounkin]

It's dark outside but I went out and adjust the cable. I'll see how it does tonight on the way home. The cable jacket looks worn from other past adjustments (before I had it). Does it need to be replaced if it keeps going out of adjustment?
I'll try again.

 

[1Byounkin]

If I adjust the bands will I get OD?

 

[1Byounkin]

OK I do get OD when driving and letting it run up to 3000 rpms. Than it will have a faint shift into OD, I guess. But still running 2800 or more rpms. Would any chemical free up anything or valves? Or just try to adjust the OD band? The truck has been driven everyday that it has been rebuilt.