Rear gear questions.

[rusty ol ranger]

From what I was told, 3.73 ratio with the 3.0 is "midlle of the road" gearing. Not sure if the 4.0 would be different, but it get's you decent acceleration and decent MPG, but not great for either. tire size would also play into the final ratio

Both are relativly small V6's that are fine with revving. A 4.10 would benifit either

 

[RonD]

The 4.0l SOHC has 207HP and 238ft/lb torque and if it has an automatic then 3.45 or 3.55 would be fine, even with 31" tires
With a Manual trans and 31"+ tire size a 4.10 wouldn't be a bad choice

 

[19Walt93]

Going from 3.55's to 3.73's will increase rpms by about 5%. 4.10's will increse rpms by 15%, a much more noticeable change. If your area is hilly like mine, 4.10's will likely allow the trans to stay in overdrive more and that would increase mileage some. In flat country, 3.55's will help mileage. If you do a lot of stop and go city driving, stop checking your mileage, it's just making you feel bad.

 

[Ranger850]

The 4.0l SOHC has 207HP and 238ft/lb torque and if it has an automatic then 3.45 or 3.55 would be fine, even with 31" tires
With a Manual trans and 31"+ tire size a 4.10 wouldn't be a bad choice

I'm not sure he's putting 31" tires on his 2wd street truck. He says he's running a 27.2" tire in a 2wd truck with an automatic transmission. From the looks of his profile pic, he may even be lowered a bit.

 

[MSGia]

I have a sohc with an auto 3.73 rear. Got about 17 mpg before the super charger.

Shorter gears can actually help increase fuel economy if you do a lot of stop and go driving. More mechanical advantage so the engine has to do less work to get you rolling. Sacrificing by getting higher cruising rpm on the highway.

Oh really? I never thought about it that way.

 

[MSGia]

Going from 3.55's to 3.73's will increase rpms by about 5%. 4.10's will increse rpms by 15%, a much more noticeable change. If your area is hilly like mine, 4.10's will likely allow the trans to stay in overdrive more and that would increase mileage some. In flat country, 3.55's will help mileage. If you do a lot of stop and go city driving, stop checking your mileage, it's just making you feel bad.

Hahaha. Central Florida is all flat, i live kinda between the city and country, but when I go to classes it’s all stop and go, my MPG will be so bad

 

[MSGia]

I'm not sure he's putting 31" tires on his 2wd street truck. He says he's running a 27.2" tire in a 2wd truck with an automatic transmission. From the looks of his profile pic, he may even be lowered a bit.

That pic is old lol, I have 4/5 now.

 

[MSGia]

So if I say my Maximum safe cruising speed was 3,250rpm, with 27.2” tires and 0.71:1 ratio, my max speeds would be 104, 99, 95, and 90mph (3.55, 3.73, 3.90, 4.10 respectively). What ring and pinion brands are good? Only one I’ve heard about being bad was Richmond gear. Also motive gear is the only brand that makes a 3.90.

 

[cbxer55]

What he forgot to say was that his truck couldn't get over 43mph before due to the 3.0, now with the 4.10s he can almost hit 50mph.

HAHA. Had it over 100 several times on I-240 here in Oklahoma City. There's a slight speedometer error due to the shorter tires, around half a tenth. I gain about half a tenth every mile. The 4.10's don't change anything because on the 98 - 00, the speedo is driven off the sensor on top of the differential.

Mine has all the s--g deleted. No muffler exhaust. CAI with three different sources of cold air supply. Chip on the computer changing the fuel trims, timing and shift points.

It does pretty darn well for what it is. Mikey Likes It!

 

[sgtsandman]

In my limited experience, 3.73 is probably going to be the best compromise with the 4.0 SOHC for combined city and highway driving and will give a little bit of a bump im mpg.

3.55 is a better highway gear and will perform best there for mpg. At least on paper.

Going from 3.45 to 4.10 on a truck netted zero change in mpg for the 2.5 Lima but get up and go was vastly improved. The poor little engine was being over worked in the hilly terrain here and couldn’t get out of it’s own way.

If you are doing more stop and go driving, the 4.10 might be a better match but that gear ratio is looked at as more of a towing, hauling, and off road gear with stock 29” tires on a 4.0 SOHC Ranger. It might be a little much for you since you are running a smaller tire and you are on flat terrain. 3.73 might be a better match for you as a result. Take a look at the gear vs tire chart in the tech section and look at the gear ratios for the tire size you are running to get a better idea what is what for the different ratios.

As another example. The 3.73s that came with my 2011 were ok with the terrain around here but is a bit anemic once I put the 31” tires on. 4.10 will put me back where I was. 4.56 will put me in the tow/haul/off road range. MPGs will go back to where they were with 4.10 and will stay about the same with 4.56 with more get up and go.

 

[MSGia]

In my limited experience, 3.73 is probably going to be the best compromise with the 4.0 SOHC for combined city and highway driving and will give a little bit of a bump im mpg.

3.55 is a better highway gear and will perform best there for mpg. At least on paper.

Going from 3.45 to 4.10 on a truck netted zero change in mpg for the 2.5 Lima but get up and go was vastly improved. The poor little engine was being over worked in the hilly terrain here and couldn’t get out of it’s own way.

If you are doing more stop and go driving, the 4.10 might be a better match but that gear ratio is looked at as more of a towing, hauling, and off road gear with stock 29” tires on a 4.0 SOHC Ranger. It might be a little much for you since you are running a smaller tire and you are on flat terrain. 3.73 might be a better match for you as a result. Take a look at the gear vs tire chart in the tech section and look at the gear ratios for the tire size you are running to get a better idea what is what for the different ratios.

As another example. The 3.73s that came with my 2011 were ok with the terrain around here but is a bit anemic once I put the 31” tires on. 4.10 will put me back where I was. 4.56 will put me in the tow/haul/off road range. MPGs will go back to where they were with 4.10 and will stay about the same with 4.56 with more get up and go.

Thanks, this is what I was looking for. If Motive gear turns out to be a good brand, I’ll probably get the 3.90 because it’s right between 3.73 and 4.10 which are both good options for me. The reviews are good, people are saying as long as you don’t have too much power that it’s a good quiet gear set when installed properly. I was also told to stay away from Richmond gear because they are loud. not that I know what a noisy differential sounds like, but I don’t want to learn the hard way lol.

 

[Roert42]

I have used Richmond gears in the past and would not hesitated to do so again.
Is suspect if it was noisy it was installed incorrectly.
Also certain gear ratios tend to be louder than other, but I can’t remember why………

 

[Blmpkn]

I can reccomend motive gears

 

[sgtsandman]

I’ve not seen anything negative on motive gear. I’ve not heard or Richmond but I also don’t work axles for a living.

 

[sgtsandman]

Thanks, this is what I was looking for. If Motive gear turns out to be a good brand, I’ll probably get the 3.90 because it’s right between 3.73 and 4.10 which are both good options for me. The reviews are good, people are saying as long as you don’t have too much power that it’s a good quiet gear set when installed properly. I was also told to stay away from Richmond gear because they are loud. not that I know what a noisy differential sounds like, but I don’t want to learn the hard way lol.

Being RWD, there is a few more options for you than there is for 4X4. Not all the ratios for the rear axles are available for the front.