Why doesn't anyone?

[rayfinseats]

Why doesn't anyone make a transfer case with a lower high gear? They are all 1:1 correct? It seems to me it would be easier than changing both gear sets in a 4x4. Anyone? anyone?

Atlas RATIOS:
Low Range: 2.0:1 or 3.0:1 or 3.8:1 or 4.3:1 or 5.0:1

High Range 1:1

[lowrollin70gmc]

I believe it has to do with the room needed for another reduction unit. When in high range the input and output can be directly driven together and in low range gear reduction does its job. To have two ratios other than 1:1 the case would be about twice as long; much like guys do with double cases on hardcore trucks.

You can also run a torque happy motor with a granny first! That's how I run 3.73s and 35s. (was 3.55 and 35s on my donor). I love my Cummins.

[rayfinseats]

That makes sense.

[special-K]

In most transfer cases low is 2:1. Even lower in some. If you have a truck 4spd 1st gear is 2:1,so when in 1st and low you have 4:1 reduction. I think things are the way they are because it's worked just fine that way for 50 years or more. People never tried to drive where you should get out and climb until more recently. For those people they can modify their rigs to suit their desires. I don't expect any auto manufacturer would build their product to rock crawl.

[Mr. 250r]

I put my 04t cummins in 4lo 1st just to see how it was compared to my 01 and man lol talk about some pulling power but not at all driveable I would like to have a 24v 6spd suburban but that'll probably never happen as far as people making them if you want an aftermarket setup there's a company that builds new cases to make the 205 lower since its weak point is basically its low I think they're called low max but I could be wrong
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[Prerunner1982]

Originally Posted by special-K

Even lower in some. If you have a truck 4spd 1st gear is 2:1

Or an SM420/SM465 with a 7.05 and 6.58 first gear respectively.

[Zoomad75]

To the average wheeling public, 2:1 low range in a 205 is just fine. The later 208 and 241's have a better ratio but it's still more than enough for the average weekend wheeler. You don't have to have a major low range for trail running. You can get a 3 speed stak or 4 speed atlas if you want to go nuts. But if you aren't doing some major rock crawling with one of those you just spent a ton and aren't even using it.

Even though my K5 has the 2:1 205, I haven't been limited by it. If I need more gear I dump the trans into Granny and plod around at a snails pace.

[hereinmissoula]

totally get what your saying and makes total sense!! 2:1 low .78:1 high or what ever..

cool

never seen it but would check it out as i have 4.57's in my 68 and only on 33's

don't go very fast lol

[rayfinseats]

Originally Posted by hereinmissoula

totally get what your saying and makes total sense!! 2:1 low .78:1 high or what ever..

cool

never seen it but would check it out as i have 4.57's in my 68 and only on 33's

don't go very fast lol

Ya I think it makes sense. It would be easier than changing 2 perfectly good rearends or gears. Technically difficult though I think.

About 10 years ago I sold my 79 chevy 3/4 ton 350/th400. The body was junk. Wish I could have afforded to keep it.

[Dunenutt]

They make a kit. 203/205 doubler...

http://offroaddesign.com/catalog/doubler.htm

[andrewmp6]

This might help http://coloradok5.com/forums/showthread.php?t=46347

[rayfinseats]

Seems hereinmissoula is the only one that even read the question. No offense.

[MadManAndrew]

Originally Posted by rayfinseats

Seems hereinmissoula is the only one that even read the question. No offense.

No, they did. You just didn't understand thier answer. And plus, that wouldn't make any sense. Why wouldn't you just make the transmission gear ratios shorter in the first place?

[Redcap]

Originally Posted by MadManAndrew

No, they did. You just didn't understand thier answer. And plus, that wouldn't make any sense. Why wouldn't you just make the transmission gear ratios shorter in the first place?

Exactly.

[lowrollin70gmc]

I read it; to have a high other than 1:1 it would take more room, as the gear reduction/overdrive unit takes more space than the direct coupling used as the 1:1. Also, overdrive gears tend to be weaker than a 1:1 and with play time in a 4x4 it would be easy to frag the gears.

Regearing isn't that bad, I'm in the middle of doing my buddies D60/14FF from 3.73s to 4.56s (other direction than you're headed). He would've easily swapped complete axles with somebody that had the 4.56s and wanted 3.73s but we couldn't find someone to do it with.

[Altec]

Just to point out, gear reduction pre-axle is a lot harder on on U-joints, drive shafts, and axles then using the axle for reduction. The less of it you have to have, the better.

[wilkin250r]

I think all the reasons have been posted.

Even though Jeeps are probably the most popular to crawl, at least 90% of them go unmodified, and other makes/models are even more so. Like special-K posted, no auto manufacturer is going to build their product to crawl. For them, designing a case with an overdrive high gear is MUCH more complex and expensive than just gearing both axles. You're looking at a re-gearing cost, they're looking at it as an initial cost. Whether they gear with 3.55 or 4.10 it's all the same cost to them.

Likewise, direct coupling is going to be easiest, cheapest, shortest, and most reliable. I can't imagine any manufacturer on earth incurring additional cost up front, as well as sacrificing reliability, just to make regearing easier and cheaper for the 5% of the population that does it.

That still leaves open the question of the aftermarket manufacturers like Atlas, Klune, ect ect. While nobody likes to spend more money than they have to, the aftermarket manufacturers aren't targeted at the "cost-conscious" crowd. The people that buy their products want strength and reliability, and size plays a small factor as well. Again, direct drive is going to be cheapest, shortest, and strongest. And not just for the transfer case itself, as Altec pointed out, you would be adding additional stress everywhere down the line. Imagine the stresses on your U-joints if your driveshaft was spinning 4.56 times SLOWER than your axles, rather than the other way around.

[wilkin250r]

The only way I could see that being reasonable is if you have the ability to change and adjust the ratio in the transfer case, so you could pick (from a limited selection of course) the drive ratio that would work for you. That way, you're only changing one set of gears in the transfer case, rather than two sets of gears in the axles.