Rear gear

This is the place to discuss DIESEL engine modifications.
bthood
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Rear gear

Post by bthood »

What would be the best gear ratio for a 5 speed diesel
2.2 Cylinder non turbo?
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puttputtinpup
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Re: Rear gear

Post by puttputtinpup »

The diesel 5speed came with a 3.73 rear end. My son and & I put a 3.42 rear end in his 82 diesel and it struggled to maintain hwy speed in 5th.
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JoeIsuzu
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Re: Rear gear

Post by JoeIsuzu »

I agree, the 3.73 hits the engine's "sweet spot" at highway speed. Any higher, and you'd have to downshift more frequently to maintain speed on hills.

Now if you don't drive on highway and you're looking for more pulling power, then the 4.10 rear end might be appealing.

Jack
bthood
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Re: Rear gear

Post by bthood »

I won’t be pulling anything and there’s no mountains or hill near by. In fact, I’ll be mostly doing city driving and very little interstate driving. So a 373 is the best choice? How would I be able to tell what my rear currently has?
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JoeIsuzu
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Re: Rear gear

Post by JoeIsuzu »

bthood wrote:How would I be able to tell what my rear currently has?

Andy told you (above). Do you have any reason to suspect the truck was originally not a 5-speed 2wd diesel?

Jack
bthood
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Re: Rear gear

Post by bthood »

This isn’t an Isuzu vehicle that this power train is going into. It’s a ford ranger.
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JoeIsuzu
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Re: Rear gear

Post by JoeIsuzu »

bthood wrote:This isn’t an Isuzu vehicle that this power train is going into. It’s a ford ranger.

Wow, that changes the whole question. Start over.

How does the weight compare to a long bed P'up? What diff ratios are available for the Ranger?

Jack
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puttputtinpup
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Re: Rear gear

Post by puttputtinpup »

bthood wrote:This isn’t an Isuzu vehicle that this power train is going into. It’s a ford ranger.

Run the vin # by the ford dealer and gather the data you need like rear end ratio and vehicle weight, etc.
bthood
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Re: Rear gear

Post by bthood »

I’ll run the vin, that was a great idea. I do know that the ranger that I’m using is about 650 lbs heavier than the pup. Im hoping thats not enough to make a big difference.
bthood
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Re: Rear gear

Post by bthood »

This power train came out of a farm truck that had totally rusted to pieces. However, the truck it’s self has less than 44 k on it. I got it from the original owner that had used it for hay and other light duty hauling needs.
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JoeIsuzu
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Re: Rear gear

Post by JoeIsuzu »

bthood wrote:I’ll run the vin, that was a great idea. I do know that the ranger that I’m using is about 650 lbs heavier than the pup. Im hoping thats not enough to make a big difference.

650 lbs? Well yeah, that will definitely make a difference. That (in my opinion) should suggest you don't want any higher gearing than the donor vehicle had. And if the Ranger has larger tires, it will need a lower rear end ratio.

Jack
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Re: Rear gear

Post by bthood »

So maybe I should pull the rear assembly from the dinner and put it into the Ranger?
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puttputtinpup
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Re: Rear gear

Post by puttputtinpup »

Check and see what ratio the ford is 1st and go from there.
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Re: Rear gear

Post by gruff54 »

bthood wrote:So maybe I should pull the rear assembly from the dinner and put it into the Ranger?


I wouldn't give up on the Ford rear yet. If a suitable ratio is available from Ford, I'd think it would be easier to change out Ford parts than swap in the Zu rear. I'm with Jack, with the Ranger being heavier I sure wouldn't go with a taller gear. Maybe there's a Ranger forum where you can find more info on available ratios?

Mike
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Re: Rear gear

Post by Halden »

JoeIsuzu wrote:
bthood wrote:This isn’t an Isuzu vehicle that this power train is going into. It’s a ford ranger.

Wow, that changes the whole question. Start over.

How does the weight compare to a long bed P'up? What diff ratios are available for the Ranger?

Jack


Knowing Ford it's probably something ridiculously high.
It's not pronounced "Ih-soo-zoo", it's pronounced "It-screws-you"
83 LS Long Box Dsl 4x4
82 Short Box Dsl 5 spd
64 Chevy C20 w/ 283 & 4 speed.
05 Sonata with a standard
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