Hopefully I'm in the correct sub-forum.

So, I just had a (budget) midlife crisis and picked myself up a '94 XL. She's got a 3.0L V6, standard 5-speed, and she's sporting a 4" suspension lift with 32" tires. Annnnnnddddd... that's all I know about trucks. I'm so brand new to this; please bear with me. Oh, and she's my daily driver.

Driving her the 200+ miles home from the guy I bought her from, I was having buyer's remorse because she would not take hills at all! I think I cried myself to sleep that night. Next day, after limping her in to work, I found this forum and saw RonD say to "Drive it like a rented mule." So I started doing that, and I can now take the hills on the freeway without losing too much momentum. I get her up to 4,500 when I'm joining the race before I shift up, then I keep her around 3,000-3,500 to maintain my speed on the ups and downs of my freeway commute.

The problem that I'm having, is when I shift into 5th gear. I know it's anathema to mention Chevy [sanitized for your protection] here, but when I was a youngster, if I threw my Camaro [redacted] into 5th, I would actually gain speed. Now, when I throw my baby into 5th, triple-loads swerve around me and flip me off as I drop 10-15 mph, my RPMs drop to a steady 2,500, and she just keeps quickly slowing down until I drop her back into 4th. The only place in my commute where 5th "works" is a pretty level couple mile stretch (or on a downhill slope); RPMs still drop, but she has no resistance whatsoever at that point. And, just to clarify, I'm not mountain driving up here. There are ups and downs on my commute, but the majority of my FWY commute is a nice legal 80 mph. I want to take advantage of that, but should I be driving 80 in 4th?! And if so, what's the point of 5th?

Is there something I'm doing wrong? Is there something wrong with my (budget) midlife crisis truck? I'm happy to supply what little other information I know in order to help you answer my questions. Thanks for everything in advance, guys!

 

Rangers don't like bigger tires, especially with stock gears in the rear axle and a 2.3 I4 or 3.0 V6. If you have higher (numerically lower) gears such as 3.55, that may be why. I have 4.88 gears in my 3.0 Ranger and it still hates my 35 inch tires. Unfortunately you just don't have the best setup for speed. These trucks were never known for it. lol.

 

32" tires is a significant tire size increase. This effectively lowers your cruising rpm. And on a low torque v6 like the 3.0, this can drop your rpm too low to keep your truck moving in 5th. What are your RPM at 80 mph in 5th? In my 3.0 at stock wheel height I have 3000 rpm roughly.

If this actually is part of your problem you will want to do a gear reduction in the rear end. Put in a taller ratio and raise your cruising RPM. This will also give you more pep around town.

Other than that your best bet is to do a full tuneup. Filters, plugs/wires, oil, coolant, trans fluid, thermostat, distributor cap/rotor, clean TPS/MAF/throttle body. Restore some of that lost horsepower.

Edit: if your cruising rpm at 80 in 5th gear is 2500 rpm (my suspicion), the difference between 2.5k and 3k rpm is about 20 hp. This is a big difference in your truck's ability to cruise at higher speeds (wind resistance increases exponentially with speed).

 

With 32" tires and a 3.0, YES you should be in 4th gear at 80.

If your truck had the stock 25" tires, then you would be in 5th gear at 80 mph.

You have 3 options
1. 32" tires 4th gear at 80 mph.
2. 25" tires 5th gear at 80 mph.
3. Re-gear the differential, to 4.56:1 gears to do 80 mph in 5th gear with your 32" tires.


Your 32 tires compared to stock tires

 

+1 To the above

The 32" tires are the issue, especially with the 3.0l engine, it, in essence, limits the use of Overdrive(5th gear), .79 ratio is too low

Its all about gear ratios, thats how an engines torque/power is transferred to the rear wheels
Any gasoline or diesel engine has a "power band", an RPM range where it makes its best power
From a motorcycle to a semi-truck, its all about the power band and the RIGHT gear ratio to stay in that power band

So lets start with you rear axle ratio, look on the drivers door, back edge for the vehicle info, then look here: https://www.therangerstation.com/tec...le_codes.shtml

Get the Stock tire size that came on the vehicle, then google it with "diameter", like "235/75R15 diameter", that will get you a number in inches, like 29"
Then get AXLE number, lets say its 86, so 7.5" axle with 3.73 ratio

Then go here: https://www.therangerstation.com/tec...ioChange.shtml

32 new tire
29 old tires
3.73 ratio
=
actual 3.38 ratio
Recovery ratio 4.12, 4.10 is closest<< this means a 4.10 rear axle would restore to original 3.73 using 32" tires

But first do this, go here: https://spicerparts.com/calculators/...rpm-calculator
Here are the ratios of your M5OD-R1 manual transmission
1st 3.72
2nd 2.20
3rd 1.50
4th1.00
5th(OD) 0.79

Lets plug in some numbers
ring and pinion(rear axle), is 3.73
tire is 32
RPMs 3,500, its a 3.0l
Trans Gear, do 1 <<4th gear
calculate

90MPH in 4th if RPMs are 3,500

Change to 5th .79, at 3,500 you would be at 113MPH
Even at 2,500rpm you would be at 80MPH in 5th, and at 2,500 the 3.0l won't hold speed very well

Try ring and pinion of 4.10, at 3,500rpm thats still 103MPH
Then try 4.56 , 3,500rpm a more manageable 92MPH

So IMO a 4.56 rear axle would be best with 32" tires, for on or off road

You can play around with it, change tire size and ratios

Its the 3.0l engine, you have to keep RPMs above 3,000, and with 32" tires its very hard to do that
Even in 1st gear you are going 24MPH at 3,500rpm, in 2nd 40MPH, 3rd is 60MPH

You have loads of TOP SPEED, but you can't use it, vehicle is way to unstable sitting that high and going for 120MPH, if you try it, please use a dash cam and put a "if found mail to: ranger-forums" sticker on it, lol

 

Your suspicions are correct, I'm cruising at about 2500 in 5th. Thanks for that info.

 

Will I end up destroying my engine keeping it in 4th at those speeds? Also, thanks for the options, I'm weighing them all right now.

 

Short answer.. NO. The engine is designed for it!
When you hit the hills just leave it in 4th and enjoy your coffee on the way into work.

 

You were spot on with the AXLE number.

Super helpful, thank you. This will at least get me headed in the right direction.

Now I want to know (after seeing how much a regear would cost) if I decrease my tire size, will I lose stability because of my lift?

 

Not really. It would look funny though to have a 4" lift and small tires. What prices are you finding for the re-gear?

 

For reference, this is my 2003 Edge (Tosion Bar) with 31's on around a 5" lift. Didn't look awful, and was manageable.

 

Wasn't looking for "small" tires necessarily, just "smaller." Just Googling re-gears, shops aren't open yet or closed on Saturdays around here.

 

Got ya! I would say a 29" tire would help and still look good. I'm not sure all the options but a skinnier tire will also help. Less rolling resistance, and less rotational weight. Just something else to look into. As if you don't have enough! LOL

 

Almost stock tire diameter. I got 255/60R15's, this is within an inch of the OEM height. I'm at 2000 rpm at 55mph in 5th. I'm at 2800 rpm at 80mph in 5th.

 

That would be bad for a 3.0l engine
But fine for a 4cyl or 4.0l because they make best torque at 2,400-2,600rpm

My 1994 4.0l with 3.73 does 2,100 in 5th at 60mph, which is fine for the 4.0l, with 3.0l it should be 3,000-3,100rpm

This is where the 3.SLOW nick name comes from, probably 70% of the 3.0ls came with automatics, and they have the same RPM shift points as the 4cyl and 4.0l, so they are just "dogs" to drive, unless you manually shift them
At least with a manual you can drive it like it should be driven, 3,000-4,000 RPM range


Say you had a Lamborghini V12, best torque/power at 5,500rpm, best horse power at 7,500rpm
And you drove it around at max 3,000rpm, then THEN complained "it has NO POWER, what a POS", lol
Same thing with the 3.0l, so having a 3.0l is EXACTLY like having a Lamborghini V12

 

i dont often disagree with you but i am going to now. if youre saying my truck needs to be at 3000 rpm at 60mph youre crazy. Theres a big aero difference between 60 and 80mph, take it from a motorcycle rider. I can cruise up hills without even going half throttle in 5th gear at 60mph, 2.1-2.2k rpm. If i were at 3k at 60 i would be approaching 4000rpm at highway speeds, even my gutless 1.6L honda civic from the 90s didnt need that many revs at 80.

Trust me on this, 2800rpm is perfect for 80mph cruising. Not too loud/buzzy, and not too weak/gutless. 2500 rpm is definitely too low for this speed though.

 

If you have a 3.0l Vulcan then you are lugging the engine under 2,800rpm

 

If you compare the tire size I have to the OEM size, it is a 100 rpm difference at 80 mph. Its literally indistinguishable from stock. So much so, in fact, that my speedometer error was corrected out by changing my tire size. My speedo is GPS/radar accurate to a tee at 70 mph. Basically what I'm saying is what I experience is virtually the same as the stock setup. Therefore what you're saying is incompatible, because you are implying the engineers built the truck wrong. I'll say it again. I can climb hills with ease in 5th gear without going anywhere near WOT. I've never had to downshift on the freeway, even in awful headwinds, except to make a speedy pass or something. It's not like I'm running 31's on my truck. Its damn near stock.

 

OK, but I am not talking about speed, or the gear, I am saying the 3.0l engine has best torque/power at 3,500rpm, regardless of speed, tire size or gearing
So for best MPG you want to be cruising near 2,800rpm, if you want power then you need to be above say 3,200rpm when accelerating thru 4,000rpm before shifting to a higher gear

If you cruise a 3.0l on the highway at say 70MPH at 2,200rpm you would be lugging that engine so MPG would be lower, with a 4cyl or 4.0l it would be fine, so you would want your gearing in the rear axle to be higher so 3.0l would be above 2,700rpm at say 70mph

 

Just to share with everyone that's been so kind to post and comment on here. Thanks for everything! You've all begun to point me in the right direction.

 

That looks like a really nice truck. Be sure to check out our how-to section for cool mods and other ideas to really make the truck your own.

 

That's a nice truck! Something else you may want to consider... If the only thing changed was larger tires, it is most likely your speedometer is reading slower than your actual speed.

 

It is. That’s already on my todo list. Thanks.

 

Man illinois isnt good to old trucks. Yours has shiny paint and no rust. Mine's frame looks like its one pothole away from snapping in half. Same year

 

A RED Ranger, best one there is

In 1994 speedometer correction is easy, just change the DRIVEN gear on the speedo cable
Your drive gear(worm gear in transmission) is 7 tooth, just FYI
3.73 rear axle ratio
32" tires
= 16 tooth Driven gear to get correct speedo readings

The driven gears are often color coded but not always,
16 tooth should be "wine"(red wine) color
Your current driven gear, for 29" tires should be 18 tooth and yellow


Car-part.com is a good place to look for used parts, like rear axles

1993 to 2009 rear axle from any Ranger or Mazda B-series just bolts in, 7.5" or 8.8", plug and play

Rear axles come in either OPEN(what you have now), or L/S
L/S = limited slip, GM calls it posi-traction, Ford calls it trac-lok, you don't "need" it, but it is a nice upgrade