T-Case UD/Low Range vs 4.88 Gears

Telly

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Recent tire change to 315's has me wanting to change my gear ratio. My initial plan was to install myself underdrive and low range gears from Cruiser Outfitters, but the gear prices have gone up significantly in the last couple years. This got me thinking of 4.88 gears instead, which I would rather have anyway. I know pulling the 3rd members is sorta a PITA but still about the same price in the end after paying someone to set them up. Any opinions on this analysis?

I had Precision Gears in my last cruiser and doesn't look like they are around anymore. Any recommendations on vendors/brands? Looks like full kits are around $1000 from several different on-line vendors.

Lastly, curious if anyone in the club want to set these up for me? Again, I'll pull them out of the axle and reinstall myself. Three Wheel Ben set me up like 15 years ago but his last post was 4 years so guessing he may not be around anymore.
 
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KC Masterpiece

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What vehicle is this for?

I have 315s on the 80 with 4.88s and 3:1 low range gears. All in all I think I get more use out of the gearing than I do out of the ARBs.

80 drives pretty good throughout CO with this setup.

I went with Sumo for the 3:1 low range and Nitro for the differentials.
 

RayRay27

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I had Slee install my Nitro 4.88s back in 2013 before the over/under drives became a popular option. Never had any issues with them at all. Slee does carry the front and rear gear sets but it looks like they are out of stock.
 

Telly

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Whoops...this question is for a 1997 locked FJZ80
 

Pz10420

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Hey Doug, if you feel like doing any testing, you could throw your 35s on my 80 with the TC underdrive gearrs and we could see how it feels. I'd be happy to help since I am considering going to 35s as well and would like to see how they feel before committing to buying.
 

jps8460

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I currently have a fully laden 80 on 35’s with stock diff ratios and 10% under drive and low range tcase gears. It ok, I do wish it was geared a bit deeper, but it manages.

I’ve heard good things about revolution gear. CruiserTEQ sells them and install kits for elocked diffs. However, you’ll need to source carrier bearing shims for the rear diff.

 
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Telly

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Wow, I bet you just barely crawl up and down rocks with the combo setup. Would be the ultimate setup fo sho.
 

rover67

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I was also looking into the 10% underdrive gears for my new to me 80 build (stock diff gearing), I was thinking staying with the 33's tho with the possibility to move to 35's maaaybe. I was wondering if the low range gears in addition to the underdrive set would be worth it. Anyhow, just saying that the feedback here is relevant to me since i'm in a similar place. I appreciate the discussion
 

jps8460

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I was also looking into the 10% underdrive gears for my new to me 80 build (stock diff gearing), I was thinking staying with the 33's tho with the possibility to move to 35's maaaybe. I was wondering if the low range gears in addition to the underdrive set would be worth it. Anyhow, just saying that the feedback here is relevant to me since i'm in a similar place. I appreciate the discussion

The low range tcase gears are one of the best aftermarket things I’ve done to my truck. The high range gears… for sure a good mod if sticking with 33’s. (I’ll probably go back to 33’s). But if you’re going 35’s and staying there I say buck up go 4.88’s and do the low range gears.

There are times still, even with Low tcase gears where my 80 is on the verge of not moving because it’s got traction and is wedged in some rocks. And the additional engine braking is wonderful.
 

Notyourmomslx450

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Big fan of crawler gears!
I run 5.29's and 37's, so i'm of no use on that aspect.
 

Burt88

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My personal opinion would be to re-gear the axles and see where you land before doing the t-case re-gear. I've done both and I see more strength in the driveline if you are able to avoid relying on the t-case for the first round of gear reduction. I'd then see if you want low range reduction in the t-case as a step two. That's what I'm anticipating on my LX470 having already put 4.88's in. High range is great but my driving style is insisting on more low range reduction.

I offer those services in my shop in Montrose for at least the foreseeable future. Coffee ain't paying the bills yet. Sorry but cant do it for free. If you want to use my shop and do it yourself I can guide you through but you'll have to commit to buying lots and lots of coffee. :coffee: :clap: ;)
 

DomOfTheDead

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Some additional notes:
-Both sets of tcase gears are installed with just presswork, no backlash or contact pattern checking. Minor clearance of the oil slinger is necessary but it was easy. I reused my bearings as they were in great shape, sourced some Toyota case seal and installed new ring gear bolts
-Installation of the 10% high range underdrive adds an additional 10% to the low range gear set reduction ratio
-I have this set up and like it, although as Jackson said, it could be lower with heavy 35s, I will be installing 4.88s at some point in my 80 too. We will be doing this Tcase gearing to Brandi's 80 shortly as well
 

Telly

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I'm with @Burt88 thinking of starting with gears first and go from there. There is a high likelihood that I'll be satisfied with the results. My previous 80 had the 35/4.88 combo with a S/C and it did great on and off road (sold it about 12 years ago). No boost on my new rig tho...maybe one of these days.

I've purchased Deep Canyon Coffee and it is delish. Tempted to head your way and stock up on joe!
 

LARGEONE

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4:88s (cryo'd Nitros) with 35s on my 80. I am happy, but you guys are making me curious on these T-case gears. I should not have read this thread!!! DOM I would love to watch/help on your 2nd install to see what is involved.
 

Notyourmomslx450

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4:88s (cryo'd Nitros) with 35s on my 80. I am happy, but you guys are making me curious on these T-case gears. I should not have read this thread!!! DOM I would love to watch/help on your 2nd install to see what is involved.
I did the part time kit too when doing mine.
I did need some press work done as mine wasn’t big enough and I didn’t have much in the line of “press tools”.
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LARGEONE

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Thing of beauty! Would love to have that on mine. Maybe after I finish the other 50 things I need to do on mine :)?
 

Lastresort576

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Is everyone removing the Tcase when doing the gears? I keep going back n forth on how I want to go about it when my gears show up in a few days.
 

jps8460

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Is everyone removing the Tcase when doing the gears? I keep going back n forth on how I want to go about it when my gears show up in a few days.
It can be done either way. I think it’s easier to take the tcase out.
 

Burt88

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Is everyone removing the Tcase when doing the gears? I keep going back n forth on how I want to go about it when my gears show up in a few days.
I recommend doing the t-case gears with the case out. It's way easier to do the work on a bench.
 
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