Truck is slow on the high way (help with gear ratios)

[rangerrabit]

Hey everyone,

I recently swapped a 1983 302 and a c6 tranny into my 85' ranger and it runs high rpms on the highway when i am only going 60 mph. I am still using the original rear differential, would that be the reason? what would the gear ratio be for a stock 85' 2.3 litre 4 cyclinder? and what would be a better ratio to have?

I am not a extremely knowledgeable when it comes to mechanic work but i am learning. thanks for your help

 

[85_Ranger4x4]

You are going to have to check and see what the ratio is, it can vary. There should be a tag on the diff cover, or you can look at the axle code and compare it with the chart in the tech library.

It is a thing you will constantly fight with a 3spd, with 31's and 3.73's mine turns about 2700rpm at 55mph.

 

[alwaysFlOoReD]

You could also try running taller tires.

Richard

 

[Fordisthebest30]

taller tires wouldn't do anything richard.

 

[straycat]

Just carry a naked girl with you and you won't think about anything else....lol.
If you look at the rear cover there should be a tag on it that tells you what size rear end and gear you have. If not, you need to look at your build sheet for the truck. You can ask somebody here to check your vin number and see what it has listed. I would just swap that stock rear end out for an 8.8 and a 4:10 gear setup. 4 cyl. stock drive train just don't hold up well with a V8 especially if you bang on it.

 

[Dan B.]

taller tires wouldn't do anything richard.

Uumm....yes they will. The taller tire will cut the gear ratio of the rears and drop the RPM's.

 

[85_Ranger4x4]

Just carry a naked girl with you and you won't think about anything else....lol.
If you look at the rear cover there should be a tag on it that tells you what size rear end and gear you have. If not, you need to look at your build sheet for the truck. You can ask somebody here to check your vin number and see what it has listed. I would just swap that stock rear end out for an 8.8 and a 4:10 gear setup. 4 cyl. stock drive train just don't hold up well with a V8 especially if you bang on it.

He is probably running comparable hp to a 3.0 and less torque than a 4.0.

I wouldn't really worry too much about the 7.5, I wouldn't pay to regear it though.

 

[pjtoledo]

so I'm guessing that counting the driveshaft revolutions won't work in this situation????

 

[adsm08]

If not, you need to look at your build sheet for the truck. You can ask somebody here to check your vin number and see what it has listed.

Because everyone still has the build sheets for vehicles that are nearly 30 years old, and the VIN system from Ford only goes back 10 years.

so I'm guessing that counting the driveshaft revolutions won't work in this situation????

Why not? That is the standard method for determining an unknown rear end ratio.

 

[adsm08]

taller tires wouldn't do anything richard.

And your avatar isn't sideways.

 

[GoodOld85BlueBalls]

taller tires wouldn't do anything richard.

From Superlift.com:

"When taller tires are installed on a truck but the axle ratios stay the same; the effective gear ratio is reduced. This means the engine is forced to operate below its power band,"

 

[SimplyTheBess]

You could drop this in it.

 

[Dan B.]

From Superlift.com:

"When taller tires are installed on a truck but the axle ratios stay the same; the effective gear ratio is reduced. This means the engine is forced to operate below its power band,"

That's what I said a few posts up. But since Superlift.com says it too, maybe now he'll believe it.

 

[Dan B.]

Very nice but still would not change his gear ratios unless he also goes with larger tires!

You could drop this in it.

 

[pjtoledo]

Because everyone still has the build sheets for vehicles that are nearly 30 years old, and the VIN system from Ford only goes back 10 years.



Why not? That is the standard method for determining an unknown rear end ratio.

It's possible you missed a bit of sarcasim in my post. We must remember, in these days of instant info (and dammned accurate info at that), hi resolution images, data bases, search engines, and really neat technical stuff, that a simple piece of chalk would have sufficed for the original answer.











yeah, I'm feelin' a bit ornery tonight. I'm practicing for next year when I turn 60.




Perry