The cost of overdrive...

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Sundowner

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It's not exactly tech, but due to the fact that I have reached and exceeded what-the-actual-f*** levels of confusion, I'm willing to ask the noobest of impolite noob questions, so...

< ahem >

For those of you that have gone to a 10% overdrive in a 70-series transfer case...what gears did you use and how much did they cost?

The reason I'm asking is, for seriously, complete confusion. I'm very new to Toyota transfer cases - and most other Toyota stuff, too, come to think of it - so I'm trying to figure out exactly which set of gears I need to do this conversion...but I'm not having much luck because most of the US-based suppliers don't list many parts for 70's. Thus, I've started e-mailing the normal shops with which everyone is familiar; I've told them what I'm looking for and have waited for responses...and the more responses I get, the more confused I get. I don't know that I've gotten any part numbers at all, thus far, but I've gotten a spread of prices that range from $400 to $950 for what should be very similar sets of gears.

That's a substantial amount of variance...but wait: there's less. I've also gotten a slew of different responses on the associated parts that are required for the project. Some people say I need idler gears and some don't mention them at all; some suggest bearings are in order, along with parts for a vacuum system, basic rebuild components, etc...and others either omit those pieces or recombine them into different arrays. The result is that I have no idea what I actually need, anymore...and I'm pretty sure that I didn't really know to start with, and am now even less knowledgeable on the subject for having tried to figure things out on my own. What's most confusing of all is my having given the exact same vehicle information to everyone - 1990 HZJ73, manual transmission, etc. - and still gotten variable replies as far as what's needed.

This all being said: what am I missing? It doesn't seem like everyone can possibly be correct with so many divergent answers having been given. So, I'm kind of lost, here.

Any input would be much appreciated.
 
I don't recall the cost but the increase in gear ratio was less than 10% (6-8%). Georg at Valley Hybrids re-geared my transfer case while he was overhauling my tranny and transfer case. I have a 3B with 3.73s in my axles and it seems like a good match for me.

Your truck may have a different setup (axle ratios, tire size, engine) so your objective solution might be significantly different from mine. However, my experience with Georg was favorable. If you have not contacted him because he in Sacramento, he could be worthy of adding to your list.

Good luck
 
I'll certainly reach out to see what he says; he's on the opposite side of the country so I can't take the rig in for him to do the work, but hopefully he can point me in the correct direction. Thanks for the lead!
 
I built a crate to fit the tranny+transfer case so it could go-n-back via freight. Worked well in that there were no issues in shipping (even the crate did not get very battered). In fact, Georg was able to get a better shipping rate than I could, so I opt'd to roll it into the bill.
 
Every set of Sumo 10% OD gears I have installed has required a smaller OD idler gear for everything to turn freely when installed. After the 4th set I started just including it in the price that I quote customers. I've put together approx 7-8 transfer cases with these in just the last year. Just my experience.

The other set that's available is from Mark's and those are only an 8% IIRC... they are more then double the price and quite noisy. I am not sure if they are still available anymore.
 
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Thanks for that, Matt; it's starting to make more sense, now. I couldn't figure out how an idler gear was optional...and it seems that honestly, it isn't. I'm fine with that; I hate spending my pennies as much as the next guy, but I very much prefer doing things once than doing them multiple times just to save money.
 

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