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Old 08-14-2020, 04:23 PM   #92 (permalink)
JSH
AKA - Jason
 
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Join Date: May 2009
Location: PDX
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Adventure Seeker - '04 Chevy Astro - Campervan
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Quote:
Originally Posted by redpoint5 View Post
Overdrive reminds me of the 1985 Volvo I drove. It had a 4 (or was it 5?) speed manual with an overdrive switch on the shifter knob. Never knew what that actually did to reduce the RPMs, or why they didn't just add another gear.

I do know coming back from Canada without the overdrive made for a noisy and inefficient trip back.
Likely similar to the 4+3 in the C4 Corvette my brother owned.

Quote:
Jalopnik: Called the “Doug Nash 4+3,” the transmission was essentially just a Borg-Warner Super T-10 four-speed with an overdrive bolted to the ass-end. That electro-hydraulically controlled two-speed overdrive was automatic, engaging when the driver let off the gas (i.e. under low load), and could be turned on and off via a button on the top of the shifter.

https://jalopnik.com/the-chevrolet-c...smi-1825119474
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