Transmission

[corywd]

I have a 1992 ford ranger xlt with a 2.9l anutomatic and it seems that my rpms are to high when im driving. For example when im doing 65mph im at like 3200rpms and my truck has overdrive so im thinking i should only be around 2000 or so rpms. Any ideas on what this might be???

 

[clifford97]

make sure the OD is on, and when was the last time you know the transmission was serviced? if you cant remember off the top of your head, its probably slipping. you can try and throw some lucas additive in there (if your one of those people who likes additives) check your fluid level, make sure its in the good range.

 

[WTF]

What's your tire size and axle ratio? I'm running 235s with the factory 3.73s and I'm right in the 2500 neighborhood doing 65 but my speedo is off due to the extra 1-1.5" tire height.

 

[sblake01]

Can you hear it shift into 4th (overdrive)? If not, your 3-4 shift solenoid might need to be replaced.

 

[WTF]

Correction: more like the high 2000- 3200 rpms at 60-65 mph but again my speedo is off from factory plus having a 20 year old speedo cable doesn't help.

 

[corywd]

I just bought the truck a couple months ago so i dont know what the previous owner did to it but i did just change the fluid and filter a month ago...thanks

 

[corywd]

Im running 30x9.5x15and the gear ratio is stock but its been like that since i bought it even with the origional size tires...thanks

 

[corywd]

Yeah i can hear it shift into all the gears...thanks

 

[kimcrwbr1]

Follow someone with a stock vehicle with a good speedo and use mph and rpm to adjust/change the speedo gear in the tranny if need be.

 

[WTF]

Im running 30x9.5x15and the gear ratio is stock but its been like that since i bought it even with the origional size tires...thanks

Okay so your tires are larger diameter than factory which in turn makes your speedo show slower than your actual speed. Use tape measure to see how close to the 30" your tires are. Your 65 is probably more like 70+. Check your door tag and use the chart on the Tech pages to get at least an idea of what the ratio of your axles are. The door tag has the factory tire size as well. Hope this helps!!

 

[BlackBII]

Maybe you have stock 4.10 gearing. Check.

Here's how.

http://www.therangerstation.com/tech_library/Axles.html

And yes, your bigger tires are making the speedo show slower than it should.