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bcoke · 09-29-2017, 01:59 AM

@jocko you are THE MAN!! I was pumped about the first chart, but you've outdone yourself with the second one. I really appreciate you breaking that down for me - I'm a total n00b when it comes to gear ratios and corresponding RPM outputs etc. I would've never been able to do this on my own, so thank you so much.

And after looking at the numbers, I agree with you that I think I can cruise at the highway speeds I need (65mph at 2200RPM is perfect) by just changing the tranny. Unless it's a LOT cheaper to get the same results by gearing down to 3.54s alone (and let me know if you think it would be), I think I'll opt for the tranny because I could knock out the highway bird and the love of manual bird with one stone.

Which brings me to what I've been looking into for weeks: the 3500 vs the 4500. I actually hadn't even heard of the 2004r or the 7004r: those might be better. I'll need to research! But my knee jerk reaction says go with 5 gears over 4.

I originally decided on the 4500 because I heard the horror stories about people blowing 3500s up, but then I talked to a guy who rebuilds 3500s to be bulletproof and has put his through hell/swears by it, and said he would build one for me (obviously taken with a grain of salt because he has incentive to sell me on it).

In looking at all the forums and online, I've heard the 3500 shifts smoother and is a more normal drive (esp in terms of gear spacing). I've heard the 4500 shifts like a dump truck and can a bit annoying how it's spaced. I'm not going to be doing any rock crawling, maybe a little mudding and light towing, but mostly just daily driving. And yet I'd hate to go through all this to do a swap and wear out a 3500 after a few years.

Thoughts?

09-29-2017, 01:59 AM	#6
bcoke Registered User Join Date: Sep 2017 Location: Austin, TX Posts: 31	Re: Advice Needed on Diff Re-Gear/Tranny Swap Dilemma @jocko you are THE MAN!! I was pumped about the first chart, but you've outdone yourself with the second one. I really appreciate you breaking that down for me - I'm a total n00b when it comes to gear ratios and corresponding RPM outputs etc. I would've never been able to do this on my own, so thank you so much. And after looking at the numbers, I agree with you that I think I can cruise at the highway speeds I need (65mph at 2200RPM is perfect) by just changing the tranny. Unless it's a LOT cheaper to get the same results by gearing down to 3.54s alone (and let me know if you think it would be), I think I'll opt for the tranny because I could knock out the highway bird and the love of manual bird with one stone. Which brings me to what I've been looking into for weeks: the 3500 vs the 4500. I actually hadn't even heard of the 2004r or the 7004r: those might be better. I'll need to research! But my knee jerk reaction says go with 5 gears over 4. I originally decided on the 4500 because I heard the horror stories about people blowing 3500s up, but then I talked to a guy who rebuilds 3500s to be bulletproof and has put his through hell/swears by it, and said he would build one for me (obviously taken with a grain of salt because he has incentive to sell me on it). In looking at all the forums and online, I've heard the 3500 shifts smoother and is a more normal drive (esp in terms of gear spacing). I've heard the 4500 shifts like a dump truck and can a bit annoying how it's spaced. I'm not going to be doing any rock crawling, maybe a little mudding and light towing, but mostly just daily driving. And yet I'd hate to go through all this to do a swap and wear out a 3500 after a few years. Thoughts?