Changing gear ratios: opinions/suggestions wanted!!

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CountKrunk

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What manual trans would you suggest? I want to accomplish the same thing. Ive had my eyes on the 4L80E but a 5 or 6 manual would be great as well.
 

Grit dog

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The OD ratios in the newer 6, 8 and 10 speeds are not much higher than what was offered in the 80s.

I'm not here to argue but turning 3k at 70 is far from useless and is acceptable.
You’re correct on top gear OD ratios, and useless was a strong word. I’ll revise to undesirable, to me, and apparently the entire automotive industry and general public buying every kind of light duty vehicle…
Or we’d still have 1:1 transmissions in front of steep gears.

One BIG difference that the 6+ speed transmissions provide even though final trans OD ratios are similar to early OD transmissions is the ability to have super deep 1st/2nd gear and very manageable gear splits through the entire range, allowing for higher final drive ratios that effectively create even higher OD ratios without sacrificing pulling power out of the hole and the full range of speed from 1 mph to terminal velocity.
Not here to argue either but again, if 1960s and 70s automotive technology was better or desired, we’d still be using it.
And anyone who says they’d rather be screaming at 3-4k rpm’s all day long across the flyover states vs 2k or less is kidding themselves, living in the past for posterities sake or just instigating a typical antagonistic Facebook type discussion.
Now if that’s what ya got and what ya can afford, I’m not knocking it, but even that is a skewed argument as non OD equipped vehicles are all classic cars/trucks by now and apples to apples, frankly more expensive than older OD equipped vehicles.
It’s not wrong to be ok with driving old iron, I love to as well. But if I’m eyeing up my 10 speed pickup, 5 or 8 speed cars or 6 speed auto diesel or my C10, K20 or CJ5 for a road trip or frankly anything that involves freeway/highway speeds for even commuting guess which ones get left at home?
 

Grit dog

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Yup, that’s about the least intrusive swap for reliability and simplicity of conversion, afaik.
But in reality most any trans swap, auto or manual in a 4wd will have some fabbing, parts collecting and figuring to be done.
I’m not well read enough to have memorized all the stuff some of the folks here have, spline counts, adapters, the right clutch hardware that works for a manual swap, etc.
There’s not really an easy button and the ultimate intended use of the vehicle figures in to what is the best path forward.
 

Grit dog

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What I mean by the last sentence is, some folks just want to be able to lower rpm’s some to go putz 55-60 mph down the county or state road and don’t leave within a 50 mile radius of home base most of the time. Where others are driving cross state or cross country on a freeway with an 80mph speed limit and would prefer not to celebrate their next birthday just getting somewhere.
All food for thought in the decision process.
 

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I'll just point out that yes newer trucks have overdrive and it is more desirable than non-overdrive and it would be silly to want an non-od trans in a new truck.

But, that's a new truck and cost would be essentially the same either way. With the older truck, you already have the non-od trans and going to overdrive would be a significant investment that you likely won't get much return on.

Now with that said...

If I was choosing between a gear swap or a trans swap, I'd definitely go with a trans swap. The reason being, I'd hate to neuter a truck by swapping in gearsets that will reduce the potential of the truck. With an overdrive trans, you can have your cake and eat it too. Either option has the potential to be very spendy.
 

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