4.0:1 Split Case Gears (1 Viewer)

[workingdog]

Yes - no change to high end.

I don’t get the link you’re making between low range gearing and highway capability. I have two rigs with 4:1 that do great on the highway at 75

 

[cruiserpilot]

Yes - no change to high end.

I don’t get the link you’re making between low range gearing and highway capability. I have two rigs with 4:1 that do great on the highway at 75

Yeah, but do the 4.0:1 have underdrive ratio’s or do the high range gears remain 1:1? I believe what he is asking is exactly what I have endured with my low range gears, will they be a noisy whine at highway
speeds?

 

[workingdog]

The high range are unchanged at 1:1 in the 4:1 cases - at least the one done by AA. I know a few split cases that are noisy (doesn't matter if they are 4:1 or not) on the highway. The Atlas 4:1 is not noisy and my 4:1 split case was noisy at the beginning, but it is more or less quiet now.

 

[WILLD420]

Like all gears, they wear in and usually get quieter. Have you tried different fluids. A lot of synthetic oils are thinner, even though they are the same weight of oil. There are tons of threads on the subject and some of the bigger shops specify a thicker dino based oil for a variety of reasons. I think I might experiment with some climbing gear lube or the 140w stuff before I would throw in the towel on a set of gears.

 

[scrapdaddy]

The high range are unchanged at 1:1 in the 4:1 cases - at least the one done by AA.

My 4:1 gears from Georg have a underdrive in high range, I believe 10%.

 

[Chuck78]

Yes - no change to high end.
I don’t get the link you’re making between low range gearing and highway capability. I have two rigs with 4:1 that do great on the highway at 75

Yeah, but do the 4.0:1 have underdrive ratio’s or do the high range gears remain 1:1?

The high range are unchanged at 1:1 in the 4:1 cases - at least the one done by AA.

Straight from Advance Adapters website page for the 4.0:1 gearsets:
"Note: This Gear set will also alter your high range ratio. The high range ratio will now result in a 10% underdrive."

716938 : Toyota FJ60/62 4.0:1 Low Range Gear Set for Transfer Caseswith a 38MM Intermediate Shaft. 34MM cases require the additional kit 716934. | Advance Adapters

4.0:1 Low Range Gear Set for 1980 - 1990 Toyota FJ60 Transfer Cases Having a 19 Spline Input Shaft and a 38MM Cluster Pin.This gear set is designed for the 38MM cluster pin case, however; we offer a stepped cluster pin that works for the 34MM case and u...

www.advanceadapters.com

What I was getting at, is that I would like to keep my high range 1:1 most likely, so that I can keep the most optimum highway cruising RPM for fuel efficiency and fuel range, and I would like to find a good low range gear set around 3.1:1 that does not underdrive the high range ratio.

 

[NookShneer]

Straight from Advance Adapters website page for the 4.0:1 gearsets:
"Note: This Gear set will also alter your high range ratio. The high range ratio will now result in a 10% underdrive."

716938 : Toyota FJ60/62 4.0:1 Low Range Gear Set for Transfer Caseswith a 38MM Intermediate Shaft. 34MM cases require the additional kit 716934. | Advance Adapters

4.0:1 Low Range Gear Set for 1980 - 1990 Toyota FJ60 Transfer Cases Having a 19 Spline Input Shaft and a 38MM Cluster Pin.This gear set is designed for the 38MM cluster pin case, however; we offer a stepped cluster pin that works for the 34MM case and u...

www.advanceadapters.com

What I was getting at, is that I would like to keep my high range 1:1 most likely, so that I can keep the most optimum highway cruising RPM for fuel efficiency and fuel range, and I would like to find a good low range gear set around 3.1:1 that does not underdrive the high range ratio.

3:1 Low Range Gear Reduction Set- Split Case 4/1986-1/1990 6x/7x Series
Fits Split-Cases with 38mm* Idler Shaft, also fits 1990+ non US 7x/8x split style transfer cases, please call with VIN for verification. 1:1 High Range. Requires minor clearancing to case housing. Made in Japan to OE Toyota specifications. Includes idler gear and low-speed output gear.
Part# TCG869031 - $650.00

3:1 kit doesn’t change the high gear cluster. It’s 1:1 in high range and won’t effect your gearing in the highway. If you use the 3.3 or 4:1 kits you will change out the high range gear cluster and have a reduction in highway/driving gearing.

The above is from Cruiser Outfitters site. Check them out.

Cruiser Outfitters

 

[workingdog]

You are right. I was wrong. From AA site "
Note: This Gear set will also alter your high range ratio. The high range ratio will now result in a 10% underdrive.

I apologize for the mis-information. I've been driving on the AA gear set for 2 years never realizing it was 10% underdrive. Now I'm going to notice it. Another vote for an Atlas when I go 4 link this summer.

 

[Chuck78]

Looks like the TCG869031 3:1 kit is going to be the ticket for me then, thanks for the link.

Any idea if it's actually 3.1:1 as others are advertised? I've seen another advertised as 3.05:1 as well. They may likely all be the same gears aside from the Mark's 4WD gears being of different origin apparently.
3.1:1 would be a nice little extra bonus in trying to squeeze a little more crawl out of it. Stock is 2.28:1 if I recall correctly. 3:1 would be noticable, but just a hair more of a change from stock would be great as well.

 

[Chuck78]

Any idea anyone of what the Terrain Tamer R151F modified fully splined 5th gear shaft mod is all about, by the way? While I have it apart... May as well build it to be the ultimate in reliability

 

[cruiserpilot]

damned iPad. Delete

 

[orangefj45]

I think this has already been addressed but hewre's the short version:
1) the 4:1 low range gear set is ONLY available in conjunction 10% UD in high range. It's common ( and to be excpected ) to have some mild gear whine in both high and low range.
2) The 3:1 low range gear set does not affect high range. Therefore, high range will sound the same, low range will ( just like any aftermarket T-case gear set ) make some mild gear noise …..

We have all the gear sets on hand, including the high range OD and UD sets as well. And we have the factory E-brake components also.

Happy to help!

Georg

www.cruiser brothers.com

shop 209-475-8808

 

[William839]

Resurrecting old thread again … so the 3:1 gear change for a 34MM 60 Tcase, will NOT effect 2 high ? I have a diesel and want to keep my RPMs as low as possible cruising on the highway. But lower the gearing when in 4L . How does the 4:1 change the 2H gearing when it’s 1:1?

 

[cruisermatt]

Resurrecting old thread again … so the 3:1 gear change for a 34MM 60 Tcase, will NOT effect 2 high ? I have a diesel and want to keep my RPMs as low as possible cruising on the highway. But lower the gearing when in 4L . How does the 4:1 change the 2H gearing when it’s 1:1?

Your question is answered multiple times in the prior posts, including the one directly before yours.

That being said. If you WANT to effect high-range AND want a lower low-range, you can use 10% overdrive or underdrive high-range gear sets in conjunction with the 3:1 low gears.

So you should consider the 10% OD High-range.

I’ve done several with the 10% OD / 3:1 low and its a nice way to get some top end without the cost of an H55 (or complication of install into, say, a 40 series)

 

[William839]

Your question is answered multiple times in the prior posts, including the one directly before yours.

That being said. If you WANT to effect high-range AND want a lower low-range, you can use 10% overdrive or underdrive high-range gear sets in conjunction with the 3:1 low gears.

So you should consider the 10% OD High-range.

I’ve done several with the 10% OD / 3:1 low and its a nice way to get some top end without the cost of an H55 (or complication of install into, say, a 40 series)

Sorry I just wanted 100% clarification, I haven’t found any OD gears for 34MM Tcase . I have a 4L80E transmission in a 4bt swapped 80 , need to get my highway RPMs down, and the T case is already out and apart for a reseal, as to why I’m looking for this option.

 

[cruisermatt]

Sorry I just wanted 100% clarification, I haven’t found any OD gears for 34MM Tcase . I have a 4L80E transmission in a 4bt swapped 80 , need to get my highway RPMs down, and the T case is already out and apart for a reseal, as to why I’m looking for this option.

The UD/OD high-range sets won’t work with a 34mm gearset.
However - you could use the AA 34-38mm stepped idler shaft to make it a “38mm case”. Or bore the case to 38mm. Or get a 38mm case.
No matter what you will have to machine the case for 3:1 gears to clear

 

[William839]

The UD/OD high-range sets won’t work with a 34mm gearset.
However - you could use the AA 34-38mm stepped idler shaft to make it a “38mm case”. Or bore the case to 38mm. Or get a 38mm case.
No matter what you will have to machine the case for 3:1 gears to clear

Copy that . Appreciate the help.

 

[orangefj45]

The UD/OD high-range sets won’t work with a 34mm gearset.
However - you could use the AA 34-38mm stepped idler shaft to make it a “38mm case”. Or bore the case to 38mm. Or get a 38mm case.
No matter what you will have to machine the case for 3:1 gears to clear

Matt nailed it!
If you want/need the OD, then you’ll want to source s 38mm case.
I’m also not a big fan of machining the 34mm cases for the lower gear sets; typically you have to tig weld 2-3 holes shut. That’s not an issue with the 38mm case.

We’re building a 38mm case fir my son tomorrow with the 3:1 low gears. I’ll post done pics. They’re going into his “HZJ25”.

Georg @ Valley Hybrids @ Cruiser Brothers

 

[orangefj45]

Here’s a preview to today’s “tech history day”.

Yesterday we rebuilt an H55F my sons HZJ25 project. We also built a new OEM 4:1 split case for our buddy Mark W.

Today we will be building two low geared transfer cases. The first one will be for my sons project and features 3:1 gears going on to his H55F we rebuilt yesterday.
The second split case we are building today has 4 to 1 low range gears. Our good friend and customer Tai Conlin will be building this transfer case onto his freshly rebuilt H55F transmission. We finished that transmission a couple of weeks ago.

Should make for a fun day. We have a number of customers and cruiser buddies joining us for today’s tech day.

Georg @ Valley Hybrids @ Cruiser Brothers

PS: did anybody notice that the H55F top cover in the pic is the “unicorn” 40-series version?!

 

[William839]

I was hoping to be able to machine my 34mm case for lower gears as the old gears are worn out and I can’t find any new ones