Non Mopar Related......opinions please.

[RustyRatRod]

My DD is an 04 Ford Ranger Edge super cab short bed, 3.0 V6 and auto. I know. But it's a good little truck. It came with 4.10 gears. It actually gets pretty decent mileage. I have figured it a few times....and it always starts with a "2" so I just stop because that's not bad. But, I would not mind it being better since gas is goin up ......wife lost her job...blah blah blah. So here's my question.

I have the chance to get a limited slip carrier....which my truck does not have......with a good used set of 3.27 gears. Do yall think that will be too much of a jump and make the truck jump back into lower gears too much going up hills and essentially cancel mileage benefits, or do you think it'll get better mileage? Right now, I am at like 2350-2400 at 65 in OD. I would like to get that under 2K. I also don't mind loosin some snap on the bottom end because I drive like an old man anyway.....wait......I am old. Damn. Any input is appreciated. Thanks yall.

 

[kb67mopar]

My opinion is to leave it alone. Some engines like to spin a bit faster and run more efficient there. If you take that engine and move the load down the power band you will probably have it lugging and using more fuel.

I found in my 02 Dakota 4.7 (I sold it) that when I put the 5 speed transmission controller in it to drop my rpm down into double overdrive that I lost mileage. Basically I dropped the rpm 400 and I lost about 2-3 mpg doing so. Part of that may have been the different transmission tune, it kept the converter unlocked at 45 mph instead of locking it like the 4 speed tune so i probably lost some mileage there. But I did not notice any improvement in hwy mileage.


PS. - Basically on the 02 Dakotas the transmission has its own computer, you can swap that computer for one out of an 03 grand cherokee 4.7 and take the 45RFE and make it the 5-45RFE (5 speed with double overdrive). This is what I did.

I still have the trans controller if anybody wants to buy it...works with the 02 4.7 powered Rams too.

 

[D575]

Is this a test.

It appears someone has hacked your account.

I agree with KB67

 

[Budnicks]

Rusty I'm sure your aware of, the 3.27:1 gear is a big drop from 4.10:1 gear, how about putting just a taller/larger diameter tire on ??, to just slightly "cut the gear ratios & the V6 isn't the best engine for TQ in the 1st place, it may ultimately defeat the purpose of changing the gears, for better mileage or what ever your trying to do, you may lose drive-ability or struggle/bog just to get it moving initially, or stay in second too much etc., there's reasons for the engineering & gearing that engine, that way, from the factory... OK now after saying all that, it probably won't hurt it much at all, especially if you driving allot of HWY/Freeway miles... But if your mostly just running around town, stop light to stop sign, grocery store/parts store trips, it's probably better to have the lower gear, just to move the truck easier, get in it's power-band quicker & more efficiently MAYBE !!... IMHFO anyway... or just by a late 90's Dodge Dakota...LOL... sorry I couldn't resist

 

[RustyRatRod]

I looked for a Dakota when I found this one. I was in a pinch and needed somethin right THEN. I really cannot complain, it's been a good little truck.

 

[Moparsmitty]

I agree also. I think that you will be disappointed with the minimal gain in mpg that you might get from this swap. These late model smaller V6s and fours are more efficient at a little higher rpm than the older bigger motors that we are used to working on. JMHO

 

[Cranky]

What's the engine's hp and torque range? Seems like it makes sense to keep the engine happy in it's torque ban to best mileage...?

 

[Photon440]

What's the peak torque of that engine? Keeping the rpms at that speed will get you your best efficiency.

Unless the new rear-end was free, I wouldn't bother. If you had to spend a couple hundred plus the work of putting it in and then saved maybe $4 per month on gas, and had a less responsive vehicle, would that really be worth it?

 

[RustyRatRod]

Peak torque is at 3900. Somehow, I don't think it will be most efficient there.

 

[fanucme]

it it were a 5 speed manual I say- yes , but since its an auto trans - No , unless you buy a tuner like a sct x3 so you can tune the transmission and that isn't cheap either.
as far as mileage that starts with 2 , It ain't broke don't fix it !

 

[Budnicks]

Peak torque is at 3900. Somehow, I don't think it will be most efficient there.

Maybe try a temporary Vacuum gauge, drive around a little & see were you make the highest levels, that's where you will want to be, I would think anyway, at-least on flat ground & cruising... I put larger {true size} 11"x32"x16" tires on my DD truck, it came with 10.5"x31"x16" Good Years stock, that were more like actually only 30" diameter/tall, on my 1999 4x4 Dakota SLT 5.2ltr Auto, it gets better mileage but now 35mph cruising up any slight hill, I have to take it out of O/D or it hunts for a gear between 2nd, 3rd & O/D all the time {I have had it re-calibrated too & use a Hypertech flash tuner} or lug the motor too much, putting way more throttle pressure to it, so I just take it out of O/D now anytime, I hit a hill at moderate speeds & I actually get better performance & fuel mileage, at the slightly higher RPM {about 400-500rpm higher at 2000 rpm in high gear instead of the 1500rpm in O/D} when it's out of O/D & don't have to press on the throttle anywhere near as hard either, to go the same exact speed @ the higher RPM... I think if you go to a bunch taller gear, like you mentioned, you may or will run into the same type of issues, especially at light throttle pressures on hills &/or slower cruising speeds, gear hunting so to speak...

- - - Updated - - -

maybe you can reprogram the trans peramiters better on the Ford than, I can with my Dodge...

 

[snakeoil24]

Leave it alone. The 4:10 puts it in the power band of your engine.

 

[daredevil]

20 something. I,d be happy.

 

[YY1]

I went through the same thoughts about my Dakota.

It's a 9 1/4 3.92, and I know lots of them came with 3.55.

So far, it's been "too much work for too little gain" as all I can find are 8 1/4 3.55 non-SG axles.

I also had to think pretty hard about the "peak torque" effeciency versus the "operating cost" effeciency.
Just because you are operating at the peak effiency of the engine does not mean the operating cost is lower.

If a 3.55 SG 9 1/4 drops into my lap, I may reconsider.

At 50 MPH in O/D I can get 23 real time MPG (I forget the RPM right now, but it's pretty low).

At 60, it's about 17, and at 70, it's about 15. Somewhere in between there is "peak torque" for the 5.9.

(I've got all the graphs and calculations, somewhere)

FTR, my average MPG is 14 give or take .2

 

[trimmer]

Hey Rusty, If you are gonna make a swap get a rear axle from an Explorer they have 31 spline axles. The Rangers have 28 splines. Make sure it is an 8.8 rather than a 7.5. But my best advice is leave it like it was built from the factory. That way every thing is calibrated to match your electronics and sensors. Also check out therangerstation.com for more info on that brand.

 

[RustyRatRod]

Thanks Bill. I am actually a member over there. Yeah, I think the only thing I am gonna do is probably install some kinda LSD or the Powertrax Lock Rite. The mileage ain't bad, but I wouldn't mind having both wheels pullin.

 

[pabster]

Rusty, I drive a Honda Ridgeline (yes, I know, I'm a traitor) with a V6, and I certainly don't get over 20 mpg. More like 16-18 around town. If you're getting over 20 in a truck, you're doing great. I know nothing about switching stuff outta your truck, but when you factor in the time, money, PITA factor, and the unknown result which may be worse that what you're running now, I also vote leave it alone. Want to bump up the mileage? Pop it in N when going down hills!

 

[Budnicks]

20 something. I,d be happy.

me too...

 

[RustyRatRod]

Well....it's not without modification. Charles did hack the step down off the outlet of the converter and was able to attach the 3" cat back onto the now 3" converter outlet. So that was a BIG loss of restriction. It necked down to 1.5" with a 1.5" exhaust pipe and now it's twice that all the way out. I can already tell it made a difference in mileage and a little in power. I've also debaffled the stock air box and sealed it to the radiator support. There's some other stuff too but I caint tell you.

 

[pabster]

There's some other stuff too but I caint tell you.

Because if you told me, you'd have to kill me. I get it.