YWST: Low Range T-Case Gear Sets for the 1980-2007 Cruisers (10 Viewers)

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Fantastic, I'm very excited to hear this! How is your gear noise?
It is there but no where near the noise what my Pro Comp xtreme mud terrains make and they are fairly quiet. Also not a nearly as loud as cutting off the exhaust resonator when I added my 4x4 labs bumper. Now, add these three things together, plus the wind noise from the snorkel, and it gets a bit noisy at 80 MPH. That said, I didn't set this up to be a luxoliner either. Eventually I will have someone mock up a new resonator and use dynomat in the rig but that is down on my list.

If I ever feel the need I may look at the new modified gear but, not sure it is worth my time at this point. I am happy with the performance gain and don't relish getting back into the case again just to make it quieter. If I ran all terrains that may change though.
 

4Cruisers

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Here are my most recent plans for my '71 FJ40 build:

'76 2F; H41 from an '84 HJ47; split transfer case with drum parking brake from an '85 BJ45; 4.11 course spline differentials; BFG LT235/85R16 ATs on 70-Series wheels. 4th gear ratio (using BFG published tire diameter) at 70 mph (as fast as I'd ever plan to drive it) is ~3,147 rpm, which is a little high. Crawl ratio in 1st gear, low range is ~39.0:1.

Alternative 1:

Same as above but with 3:1 Sumo gears in the transfer case and 3.70 fine spline differentials. 4th gear ratio (using BFG published tire diameter) at 70 mph (as fast as I'd ever plan to drive it) is ~2,832 rpm, which is just right. Crawl ratio in 1st gear, low range is ~53.8:1.

Benefits of springing for the Sumo gears (I already have a spare set of FJ60 fine spline 3.70 differentials with the earlier, correct driveshaft bolt pattern):

Lower (better) highway rpms, lower (significantly better) crawl ratio, and somewhat stronger pinions.

Anything I haven't considered?
 

cruiseroutfit

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Here are my most recent plans for my '71 FJ40 build:

'76 2F; H41 from an '84 HJ47; split transfer case with drum parking brake from an '85 BJ45; 4.11 course spline differentials; BFG LT235/85R16 ATs on 70-Series wheels. 4th gear ratio (using BFG published tire diameter) at 70 mph (as fast as I'd ever plan to drive it) is ~3,147 rpm, which is a little high. Crawl ratio in 1st gear, low range is ~39.0:1.

Alternative 1:

Same as above but with 3:1 Sumo gears in the transfer case and 3.70 fine spline differentials. 4th gear ratio (using BFG published tire diameter) at 70 mph (as fast as I'd ever plan to drive it) is ~2,832 rpm, which is just right. Crawl ratio in 1st gear, low range is ~53.8:1.

Benefits of springing for the Sumo gears (I already have a spare set of FJ60 fine spline 3.70 differentials with the earlier, correct driveshaft bolt pattern):

Lower (better) highway rpms, lower (significantly better) crawl ratio, and somewhat stronger pinions.

Anything I haven't considered?

Sorry, I never saw this reply until today. Did we chat on the phone about this?
 

cruiseroutfit

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T-Case season! These 80 and 100 Series transfer cases got some major love this last week. Total refresh with all new bearings, seals and gears. Both cases received our Japanese High-Range 10% Underdrive gears offering more get up and go, 3.1:1 Low Range Gears offering a 33% reduction in low range and part-time 4WD conversion kits to allow true 2WD or 4WD function out ot the t-case. Give us a shout if your t-case needs some love, you can even send it to us for a full overhaul and upgrades as needed. 801-563-1277 or info@cruiseroutfitters.com

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Has anyone done this in their 100 series that can chime in on their satisfaction of the underdrive and low range gear reduction set for their t case? Also curious what the total cost ends up being after new seals oil etc.
 
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I can comment on the low range gears. Rig before gear install 2000 LC, 4sp, 4:30s, front and rear air lockers, heavily built. When I installed the low range gears I also installed 4:88s. I had about 10 years of offroading with it before the gear install and about 3 years since. They have been a great addition, wish I had done it sooner. I find I don't use lockers as much, as lower gearing does the work. In 4Lo use 2nd gear and 2nd start where I used 1st, and now just use 1st for tougher stuff.
I did the install myself and also replaced a couple of bearings and the t-case oil pump as I didn't like the look of them, so can't give you a cost for having it done.
If you have a later model with the 5sp, it will be different and you may not need the diff ratio change to get similar results.
 

cruiseroutfit

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Has anyone done this in their 100 series that can chime in on their satisfaction of the underdrive and low range gear reduction set for their t case? Also curious what the total cost ends up being after new seals oil etc.

I've sold and installed a handful @ Cruiser Outfitters. In fact I don't know of anyone else in the US offering the conversion parts to put the gears in the 100?

Perhaps @mderrick can chime in as well? He has them in his personal 100.
 

JunkCrzr89

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In fact I don't know of anyone else in the US offering the conversion parts to put the gears in the 100?
Technically, I think YotaMasters (and maybe Marlin Crawler?) keep stock of the low range gears (Trail Gear version) for 80 and 100 series and do installs at their shop, but they do not carry the underdrive or overdrive gears that you guys have or the Sumo version low range gears. I'm not aware of anyone in the US that carries the UD/OD gear sets, Sumo low range gears, or complete t-case rebuild kits for 80/100 series other than you 👍
 

cruiseroutfit

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Technically, I think YotaMasters (and maybe Marlin Crawler?) keep stock of the low range gears (Trail Gear version) for 80 and 100 series and do installs at their shop, but they do not carry the underdrive or overdrive gears that you guys have or the Sumo version low range gears. I'm not aware of anyone in the US that carries the UD/OD gear sets, Sumo low range gears, or complete t-case rebuild kits for 80/100 series other than you 👍

Sorry, I was referring to the UD/OD High Range kits. To my knowledge we are the only ones offering and fitting those in 100/470's. Definitely some other great folks doing the low range gears too.
 

Will Van

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Are the only gearing options offered for the HF1A transfer case the 3.1:1 low range gear set? Is there a high range overdrive set available too? Can they be used in combination/simultaneous (overdrive high range and underdrive low range)?

Do you have any core HF1A manual shift cases in stock for rebuild?
 
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