02 S-10 gearing question.

[aerohead]

Originally Posted by deejaaa

True. Although I couldn’t notice any reasonable gains in mileage in the other truck it at least brought rpms down enough to reduce strain on the engine.

Many decades ago, HOT ROD Magazine did a project with Ford Ranchero, which included adding a Gear Vendors OD unit. I may have discussed it in my 'lectures.'
I don't have that data at hand, but my memory is that, it was well worth the trouble.
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Back in 1976, messengers reported that a 28% overdrive would produce a 19% improvement in fuel economy.
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I swapped out a 3-speed 1:1 transmission and 4:56 rear end, for a 4-speed OD trans and 3.50:1 axle in my grandad's '61 DODGE D-100, which along with steel radials and some aero brought the indicated 55-mph top speed & 11.0-mpg, up to an indicated 91-mph top speed, and 21.5-mpg.
It was just a leap of faith, but it worked out.
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We can't have any 'a priori' knowledge of what gearing would do for you.
If you were to do any significant 'streamlining' to the Chevy, the PhDs' would tell you that taller gearing would be mandatory.

[deejaaa]

Your making it hard to decide what to do.....

[freebeard]

Throw the I Ching?

[aerohead]

From: HOT ROD Magazine, December, 2008, pages 102-105, by Christopher Campbell.
* Their project truck was a 1967 Ford Ranchero GT.
* With C4, 3-speed automatic, pre-lockup trans.
* OEM, @ 65-mph = 13.0-mpg.
* With street-rod mods, 17.0-mpg @ 65-mph.
* Adding electronically-shifted 0.78:1 overdrive = average 19.5-mpg. As high as 20-mpg, once.
* Average 14.7% mpg improvement.

[aerohead]

I had a Car and Driver article for the 1994 model year GMC Sonoma SLS ( a mechanical clone of the Chevy S-10 Super Sport, regular cab, with 4.3-liter V-6, 195-bhp @ 4500 rpm, 5500 rpm redline, and GM 4L60-E, 4-speed overdrive automatic trans, with 3.42:1 ring & pinion, P 215/ 65 HR-15 tires.
--------------------------------------------------------------------------------------* In 4th-gear, the truck is geared for 140.4-mph @ rated power.
* 2,500-rpm, in 4th = 78-mph.
* The truck achieves a governed top speed of 112-mph, in 3rd-gear, @ 5150-rpm.
* In 4th-gear, the truck holds 112-mph, @ 3,600- rpm ( 80% of rated power, and peak torque.
* 4th-gear = 31.2-mph / 1,000 rpm @ engine.
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* Both a Borg-Warner T5 manual five-speed overdrive transmission, and New Venture Gear manual five-speed were available, depending on engine package.
I don't have any data for the NVG transmission.
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As of 1975, Borg-Warner had engineered a 5-speed 1:1 output shaft unit, which would be used in conjunction with a lower numerical ring-and pinion to achieve the desired 'overdrive' final drive ratio, but without the 2% attendant mechanical loss of a typical OD transmission. Not used by GM as of 2004, when the S-10 went out of production.