POLL: 4:1 split case noise level

[CruiserTrash]

I've been pondering regearing my transfer case for a few years now. Every time I'm on a trail I think about how nice it would be to have some more control whether ascending or descending, or going over some technical rocks. In the meantime, I've also been pondering moving to 35" tires from my current 33s. The 4:1 transfer case gears with 10% high range underdrive would make the magic happen for me - I already have 4.11 gears in the diffs and the t-case gear set would make the numbers work out almost perfectly.

*I daily drive my 60, hence the concern. If it was a trail-only rig I wouldn't care. I can add sound deadening under the transmission tunnel carpet, but I've heard that's not even enough. If 4:1 gears aren't tenable in a daily, I may settle for the 3.3:1 or 3.1:1. I've heard those are much friendlier for daily driving.

 

[John McVicker]

Maybe this will help…I’ve got a 3:1 T-Case gear & it is noticeably louder than stock. I would guess that 4:1 is even louder.

However…for me it’s a non issue…don’t know about you but I’m fairly hard of hearing…AND for me at least, the xtra noise is well worth it to get the advantage of the better crawl ratio. Well worth it!

Hope this helps.

 

[CruiserTrash]

Maybe this will help…I’ve got a 3:1 T-Case gear & it is noticeably louder than stock. I would guess that 4:1 is even louder.

However…for me it’s a non issue…don’t know about you but I’m fairly hard of hearing…AND for me at least the xtra noise is well worth it to get the advantage of the better crawl ratio. Well worth it!

Hope this helps.

That is helpful John, I appreciate it. A little extra volume is fine but I keep hearing horror stories from people with the 4:1 gears. Being in the San Juans recently, it was proven to me again that I'd like more control.

 

[John McVicker]

Control is wonderful. I forget the exact number but my crawl ratio doubled from stock of somewhere around 26:1 to somewhere around 54:1. This makes a major league difference when wheeling. And your proposed 4:1 would be even more advantageous.


EDIT. I also have an H41 transmission which gives me a lower 1st gear vs stock H42.

For me this is a good combo. I got this Trany/t case combo from Dave Gore @lcwizard many years ago.

 

[CruiserTrash]

Control is wonderful. I forget the exact number but my crawl ratio doubled from stock of somewhere around 26:1 to somewhere around 54:1. This makes a major league difference when wheeling. And your proposed 4:1 would be even more advantageous.


EDIT. I also have an H41 transmission which gives me a lower 1st gear vs stock H42.

For me this is a good combo. I got this Trany/t case combo from Dave Gore @lcwizard many years ago.

I've been playing with this really good gear ratio calculator for months now. It's very in depth. I'm currently at 33:1 crawl ratio with stock 2:1 gears and 4.11 diff gears out of an FJ62.

3:1 gears get me to 45:1
3.3:1 gears get me to 48:1
4:1 gears get me to 58:1

Obviously the 4:1 would be more advantageous purely for off road control. For the amount of time & money, the 3:1 and 3.3:1 gears only net me about ~40% lower ratio, which isn't nothing. But the 4:1 gears are another 75% lower than where I'm at and that's significant. The 4:1 gears are 10% underdrive in high range as well, which sort of "unlocks" the ability to run 35s. That's really why I'd like to run them - I get two wins out of it.

I think an H55 is going to wind up in my 60 eventually and with the extra low first gear that brings me to: 62, 66, or 80, respectively, which would be LOTS of control. I'm not looking to build a hyper-technical crawler with some crazy crawl ratio, but better is better.

 

[toy_tek]

Maybe this will help…I’ve got a 3:1 T-Case gear & it is noticeably louder than stock. I would guess that 4:1 is even louder

The louder noise is overall or just when using low range?

 

[bj70bc]

i have these gears waiting on the shelf to go in 3.3-1 and 10%underdrive, i think they need to go in too im on 34 35" tires

 

[John McVicker]

The louder noise is overall or just when using low range?

Higher noise overall but for me anyway mainly in 1st & 2nd.
But I really like the lower crawl ratio, going up a hill/obstacle BUT also great for descending a steep hill. Much easier on the brakes. I really don’t even notice the noise anymore.

 

[matubrembrem]

Not 4:1 but I put a new h55 and 3.3:1 low 10% ud high sumo gears in my 60 over 3 years ago and the noise in high range is hardly noticeable. It does have more whine than stock in low range. It’s on 35’s and I have the stock 3.70’s in the diffs. I also didn’t have carpet in the truck for all that time. Just foil backed butyl throughout. From what I read at the time, a lot of the noise complaints were from the older mark’s gear sets.

 

[matubrembrem]

Also, you’re probably already aware of this, but the 34mm split case will end up with some holes when milling clearance for the 3.3:1 gear set. I had to have mine welded up.

 

[matzell]

Jim,

I have the H55f and a 4:1 set in my 40. Low range gear whine is loud, 4th and 5th gear like on Camp Bird Road but not a deal breaker. I really do not notice it in High range. I think my 35" mud terrains drown it out

I would do it over again in a heartbeat.

 

[CruiserTrash]

Jim,

I have the H55f and a 4:1 set in my 40. Low range gear whine is loud, 4th and 5th gear like on Camp Bird Road but not a deal breaker. I really do not notice it in High range. I think my 35" mud terrains drown it out

I would do it over again in a heartbeat.

Another person who enjoys rowing through the whole transmission while in low range!

Honestly, low range whine isn't going to bother me. I daily drive the truck and 90% of the time it's on pavement cruising around town - it's the noise in that scenario that would be the desal breaker.

@matubrembrem I hear you on the 34mm case. That's what I currently have, but I would get a 38mm case and rebuild it with the new gears that way I can prep everything ahead of time and cut down on swap time. Honestly, after doing it once with the transmission out, I'd probably just rebuild the case on the truck. I'm lifted high enough that it's not horrible sitting crosslegged underneath ... and if I have to stab a pilot bearing again I'm not gonna have any hair left on my head!