Possible gear change in new to me Ranger

[hat_man]

Hello everyone. Long time no see lol.

I had to retire the old Ranger at just shy of 300k miles. Loved that truck but it was having too many expensive problems. I only paid $4,000 for it and drove it for 10 years, it didn't owe me a dime.

I now have a 2003 Ford Ranger 2.3l Duratech with 3:73 gears. My drive is the same about a hundred and twenty-five miles a day and I don't tow anything. I'm thinking about changing the gears in the rear end to either a 3:55 or 3:45. It looks like both are options for the 7.5 open rear end. (Axle codes 85 and 84 respectively)

Would I be giving up too much passing power with the 3:45 (not that a little 2.3 has any real power LOL) ? I'm leaning towards the 3:55.

I know it's not a huge difference between those two and 3:73 that's in there now. Any thoughts or advice?

Thanks.

[JRMichler]

Manual or automatic?

Put in a ScanGauge or Ultragauge and monitor the vacuum. If you are running 15" to 20" Hg during highway cruising, you would definitely benefit from a taller gear. If you are running 5" to 10" Hg vacuum during highway cruising, you are right at the best rear end ratio. Note that SG reports MAP, so 20" vacuum is about 5 PSI MAP.

As for passing, that's what the other gears in the transmission are for. Also driving skills like anticipation and getting a running start.

In the world of gas mileage, it is a good idea to know how much you are held up by not passing a slower driver. For example, if you normally drive 60 MPH and you are stuck behind somebody driving 55 MPH for 10 miles, your total delay is less than 55 seconds.

[Daschicken]

I agree with JRMichler above, size your differential ratio for cruising. Its quick and easy to change gear, its not quick and easy to change your differential ratio.

Assuming 5 speed manual...At 70 mph with the 3.73 gears you should be running 2529 RPM, not bad.

3.55: 2407 RPM

3.45: 2340 RPM

Go big or go home!

[Baltothewolf]

Unless you can do it for really cheap, I say it isn't worth it. However, if you can find someone trying to trade a 3.45 or 3.55 for a 3.73 then it's worth it. Unless you can get your hands on a 3.03 or lower, I wouldn't do it. Too bad it's not a 8.8, those came in 2.73. My Mustang (AOD auto) would cruise at 1600 or 1700rpm at 70.

[Hersbird]

You might actually be able to find an 8.8 with the highway gears for cheap.

[jcp123]

Originally Posted by Baltothewolf

Unless you can do it for really cheap, I say it isn't worth it. However, if you can find someone trying to trade a 3.45 or 3.55 for a 3.73 then it's worth it. Unless you can get your hands on a 3.03 or lower, I wouldn't do it. Too bad it's not a 8.8, those came in 2.73. My Mustang (AOD auto) would cruise at 1600 or 1700rpm at 70.

Heck, the 9" rear had 2.73s in my '68 Mustang many moons ago. Kept me at 2200rpm@60mph. Considering I lacked both overdrive and lockup (C4 trans), it wasn't too shabby.

Weren't some 7.5's in Fox bodies? Makes me wonder, if the dimensions aren't too different, a swap to an 8.8 might be viable on a Ranger, though I won't exactly say it would be the easiest thing in the world.

[hat_man]

I think the only other options for taller gears in the 7.5 open would be 3:27 or 3:08. With only about 130hp (?) the 3:27 and almost for sure the 3:08 would be too much gear to get rolling from a dead stop. I still do some in town driving and don't want it to be a dog at stoplights.

I was planning on a whole rear end swap rather than just trying to swap the gears. Much simpler. I thought about an 8.8" from an Exploder but IIRC there are issues with the emergency brake and maybe some other things. I wanted as straightforward a swap as possible.

The old truck was getting 28+ MPG before the "issues" started. I did some "mods" from our list and at it's best was getting 30 MPG consistently. The "issues" have cost me over $600 and it's still not running right. 28 mpg was still really good for a truck with nearly 300k miles on her. The new truck has 75k miles and a better engine. I got 28 mpg on the way home from the sale and I haven't even started with any mods. I know they are capable of over 30 mpg.

It's just a matter of making a decision on 3:45 or 3:55 gears now. Anyone else have any real world experience?

Thanks.

[19bonestock88]

Around town you shouldn’t notice the taller gearing much... if you don’t haul much extra weight, I’d go for the 3.08 ratio...

The 2.3 Duratec has plenty of power to handle the difference around town and aeromodded, the difference on the freeway shouldn’t matter much as far as holding speed

[Ecky]

As JRMichler says, you have a whole gearbox full of choices for passing. I pass in 3rd gear on the highway, and often 2nd in town. I need 4th or even 3rd for climbing even shallow hills. As long as you can maintain speed in most driving conditions in top gear, taller gearing will be beneficial.

[Hersbird]

Lots of Rangers have an 8.8 already. I was going to swap an 8.8 into my 68 Plymouth Barracuda because of the outrageous cost of narrower 8 3/4 inch mopar diffentials ($1200 was common) and it would have given me 4 wheel discs as well. I had already swapped my front bolt pattern to newer 5x4.5 discs so it would have matched that as well. The sets I were looking at were 3.73, limited slip, with the disc brakes for around or even under $500. Explorers or v6 Rangers were the donors.