rear body mounts (5 Viewers)

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Just read up on that. Probably wrong but it looks as tho it is built for a 4 speed and 34mm idler shaft, no?
Completely different bearing system on the idler, they use tapered rollers instead of bushings and they slide on a 34mm shaft, if you have a 38mm case you just use a 2mm bushing to adapt it over the 34mm shaft.

The high gears start getting a little noisy around 85 MPH and anything over 95 MPH for an extended time they are a bit loud but I just turn up the radio, for most of my driving 75MPH or less they don’t make any more noise than my factory box.
 
Does look cool - says can fit between a H55F and 19 spline split case. The only thing I’m not sure about without searching very deep is if the input spline count has anything to do with the idler shaft size. By my understanding, an H55F will only bolt up to a 38mm idler shaft split case.
 
We stock all the gears :D

Mark's & Sumo!
 
So the gear set you linked @J Mack says for 10/82 - 10/84 5spd trans with 34mm idler shaft. Must have been a transitionary stage. That’s good info especially if you pick up a used H55F, or happen to have one from those years. You could use an 82-84 trans with a 34mm or 38mm case. But the later trannies can only run 38mm, correct?

C68DCCA5-3D55-4DCD-9304-84FD52E014A5.jpeg
 
You could use an 82-84 trans with a 34mm or 38mm case. But the later trannies can only run 38mm, correct?

If you go to the Mark’s link I posted and download the instructions you’ll see the sleeve to adapt their 34mm shaft to a 38mm case.

Somewhere in my build thread I have detailed pictures of the Mark’s kit.

This isn’t another tirade @wngrog he keeps asking questions, blame Rush.:flipoff2:
 
3:1

☝ No noise in hi range, because you don’t change the hi range gears.

If you get noise it will only be on the trail.

Add a black box down the line if you aren’t satisfied with the low gearing. (Would need to upgrade the driveline strength as @RUSH55 indicated)

You are saying the 3:1 Marks gears are quiet because they use the stock high range gear?

Trying to keep up. The Black Box was in here before this comment and the. JMac started in with his 85-95 mph stuff
 
Fwiw, we can do the 3:1, 3.3 & 4:1 Sumo Japanese gears in either the 34mm or 38mm case. They offer a conversion idler shaft and in some cases we combine those with additional parts to fit the earlier 34mm case. The has been some detailed threads on the 34 vs. 38 mm t-cases but long and short, both are great options and you're not going to break anything in a 34mm that wouldn't suffer the same fate in a 38mm. Wear on the 34mm idler shaft proper is/was the issue and after 200k it's a marked difference.

1567522488043.jpeg


You'll notice the 3:1 keeps the high range at 1:1 where you get some underdrive out of the 3.3:1 and 4:1 options. For many this is welcome, for others it is not. The underdrive is needed in HR for the 3.3/.4.1 in order to get the input ratio workable for the low range to get that low. For those that like their existing factory low but want a high range overdrive (faster speed) or underdrive (more power), we offer a 10% kit for either direction. As noted above these can be fitted to the 34mm case with some conversion parts.

In addition to the Sumo Japanese gears, we do stock some of the Marks 4WD gears out of Australia. They are less common these days as the Sumo options have surpassed their offerings but they do have a few ratios that are worth considering.

We stock more gear options in the US for the split case than anyone and can offer any of these gears in a brand new t-case too! :cool:
You can rear more about them here on Mud: YWST: Low Range T-Case Gear Sets for the 1980-2007 Cruisers
 
You are saying the 3:1 Marks gears are quiet because they use the stock high range gear?

Trying to keep up. The Black Box was in here before this comment and the. JMac started in with his 85-95 mph stuff

Correct. I have Sumo 3:1 in my 38mm case w/h55 in my 60.

The 3:1 kits provide deeper gearing only on the low cluster. Leaving the stock gearing on the hi cluster.

Deeper gearing on the trail (louder gear noise) but not significant change on the highway.

Side note: coming from the stock 4speed and stock split case gearing. The change to the h55 and 3:1 gives an additional gear and a half below stock 1st Low.

With the stock 4spd and stock split case gears, the 1st gear feels like it falls between the h55 and 3:1’s 2nd and 3rd gear.
 
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Fwiw, we can do the 3:1, 3.3 & 4:1 Sumo Japanese gears in either the 34mm or 38mm case. They offer a conversion idler shaft and in some cases we combine those with additional parts to fit the earlier 34mm case. The has been some detailed threads on the 34 vs. 38 mm t-cases but long and short, both are great options and you're not going to break anything in a 34mm that wouldn't suffer the same fate in a 38mm. Wear on the 34mm idler shaft proper is/was the issue and after 200k it's a marked difference.

View attachment 2074545

You'll notice the 3:1 keeps the high range at 1:1 where you get some underdrive out of the 3.3:1 and 4:1 options. For many this is welcome, for others it is not. The underdrive is needed in HR for the 3.3/.4.1 in order to get the input ratio workable for the low range to get that low. For those that like their existing factory low but want a high range overdrive (faster speed) or underdrive (more power), we offer a 10% kit for either direction. As noted above these can be fitted to the 34mm case with some conversion parts.

In addition to the Sumo Japanese gears, we do stock some of the Marks 4WD gears out of Australia. They are less common these days as the Sumo options have surpassed their offerings but they do have a few ratios that are worth considering.

We stock more gear options in the US for the split case than anyone and can offer any of these gears in a brand new t-case too! :cool:
You can rear more about them here on Mud: YWST: Low Range T-Case Gear Sets for the 1980-2007 Cruisers

Kurt, as usual, this is pretty cool info.
Can you offer any guidance/hearsay on the noise level your customers experience from the Sumo gears?
 
Correct. I have Sumo 3:1 in my 38mm case w/h55 in my 60.

The 3:1 kits provide deeper gearing only on the low cluster. Leaving the stock gearing on the hi cluster.

Deeper gearing on the trail (louder gear noise) but not significant change on the highway.

Side note: coming from the stock 4speed and stock split case gearing. The change to the h55 and 3:1 gives an additional gear and a half below stock 1st Low.

With the h55 and 3:1 the stock 1st gear feels between h55 and 3:1’s 2nd and 3rd gear.

Being the rare person that prefers a stock 4 speed, 3.70s and 33’s for all around drivability a set of 3.0 gears in my case would be clutch for the 2% of the time I need to slow down.

Great info. I thought all of them were loud.
 
Trying to get my brain around this statement but it just ain't happening...

Sorry, was typing while walking the dog.

With the stock 4sd and stock split gears the 1st gear feels like it falls between h55 and 3:1’s 2nd and 3rd gear.
 
Kurt, as usual, this is pretty cool info.
Can you offer any guidance/hearsay on the noise level your customers experience from the Sumo gears?

Great question and one we get somewhat regularly with the many 4x/5x/6x/7x/8x/10x t-case gear options we have. Fortunately the noise (and we all acknowledge there is added gear noise similar to an agressive tire) isn't bothersome for most. The noise levels of low range t-case gears have been noted starting with the early days of the Marks Gears in 4x and 6x cases, the AA Orion cases and since the 8x gears hit the market a decade plus ago. 8x and 10x setups seem to be the most sensitive to the noise and rightfully so as the interior of their vehicles is much quieter than any 4x/5x/6x/7x and the added gear train noise can be noticeable. Most 4x customers thing the overall noise of the split case and any gearing changes is much quieter than a 1pc case :D
 
Marks recommends Castrol Optimol Optigear to help with any added gear noise, I couldn’t find it local so I’ve been running the same oil I use in my NV4500 trans. ACDelco 10-4059 GL-4 75W-90 Manual Transmission Fluid.

I can’t tell you if this is good or bad but mine is not overly noisy at normal driving speeds.
 

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