4.0:1 Split Case Gears

[vk7ybi]

I'll be happy to chime in ......

The gears sold by AA, Cruiseroutfitters and other vendors like myself are all marketed as "Sumo Gears". We all get them from the same vendor and they're made by a very reputable gear manufacturer. The same company that makes the gears for the Orion amongst many other products. And they've been doing so for many decades ...... great quality and reliability.

Thanks Georg..
I had a suspicion the gears from the various sellers were made in the same factory. I do run the 4:1 Orion in my 40, and more than happy with that as far as noise is concerned.

 

[Cruiserdrew]

Thanks Georg..
I had a suspicion the gears from the various sellers were made in the same factory. I do run the 4:1 Orion in my 40, and more than happy with that as far as noise is concerned.

No kidding. Orion is much quieter than the transfer case it replaced.

 

[vk7ybi]

No kidding. Orion is much quieter than the transfer case it replaced.

KI6MIE? I'm VK7DB, was VK7YBI when I signed up..

 

[NookShneer]

Please show one instance in which there was damage as a result of the case being machined. Regardless, both sets of gears state that there is case machining required.



This is pretty childish.



If they're not both made in the same factory (I would not be surprised in the slightest if they are) then you can safely assume that you will get a quality product from either vendor. Both have a long history of good products.

Just sharing what I heard from Adam at Torfab, not my personal experience myself. He simply said they have had customers with the Sumo sets have issues with case weakness.

 

[orangefj45]

I'd like to see that too. I've built well over 50 cases with these gears with ZERO case failures.

Georg @ Valley Hybrids & Cruiser Brothers

 

[dare]

I haven't seen the 3.1:1 Japanese made gears before. Pity It seems like they're 7% under drive, I'd buy them today if they were standard high range or overdriven. Does anyone know the exact ratios?

3:1ish low with 5-10% overdrive would be my ultimate gears. Good gear spread in low with the ratios I want, high enough top speed in low for the trails around here. I don't drive really crazy trails so I don't need a super crawler gear.

Having seen how Marks Adapters dealt with a friends issues and hearing a few stories I don't intend on ever dealing with them, besides I can't afford them and many people say they whine. They do come in nice ratios though.

 

[vk7ybi]

I haven't seen the 3.1:1 Japanese made gears before. Pity It seems like they're 7% under drive, I'd buy them today if they were standard high range or overdriven. Does anyone know the exact ratios?

3:1ish low with 5-10% overdrive would be my ultimate gears. Good gear spread in low with the ratios I want, high enough top speed in low for the trails around here. I don't drive really crazy trails so I don't need a super crawler gear.

Having seen how Marks Adapters dealt with a friends issues and hearing a few stories I don't intend on ever dealing with them, besides I can't afford them and many people say they whine. They do come in nice ratios though.

Its a bit of a juggle to find the right combination I think.. I have 4.88 diff gears, and with 4:1 transfer gears with the 10% underdrive, I'll be something like 25% underdriven. I run 35" wheels at the moment, and that makes me about 10% slow on the speedo.. The 4.88s are for my 40, so when they eventually find their way into there, I might run 4.56s in the 62 on 35s.. Cant justify the mods necessary to run 37"s on the 62.
I have similar feelings regarding Marks.. I dealt with them when I got the Orion into Aus, and they werent very friendly, so went elsewhere.. Also heard about the noise issues too..

 

[cruisedeisel]

I almost ordered the Advanced adapters 4:1 yesterday. But it came to $1900 canadian for the gears, 34mm step down pin and a TC rebuild kit. I chickened out. Maybe when I get a raise. lol!

 

[orangefj45]

I almost ordered the Advanced adapters 4:1 yesterday. But it came to $1900 canadian for the gears, 34mm step down pin and a TC rebuild kit. I chickened out. Maybe when I get a raise. lol!

Let me know when you're ready to purchase ....... I'm pretty sure we can do better on the price.

Georg @ Valley Hybrids & Cruiser Brothers

 

[orangefj45]

I've had similar experiences with Marks and have witnessed the gear noise in a couple of vehicles so I've chosen not to install them at our shop.
Georg @ Valley Hybrids & Cruiser Brothers

 

[cruisedeisel]

Thanks Georg! PM me with a price plus shipping to vancouver island and I will get back to you.

 

[dare]

If anyone is interested I did email low range off road asking the exact ratios of the 3.1:1 gears.

1.07 high and 3.1 low.

 

[Komanche]

Thanks

 

[dare]

If anyone is interested I did email low range off road asking the exact ratios of the 3.1:1 gears.

1.07 high and 3.1 low.

Thanks

Well actually. I enquired with sumo gear themselves and they said Low Range are wrong. The high range is left standard. In the 3.1:1 kit only the idler and low range output gear are replaced so high range cannot be altered.

 

[Well Sorted]

Hey guys, I just finished my LS swap and am running the 4:1 low range gear set from AA. I built the tcase myself and followed all the FSM specs, but it seems awfully noisy with gear whine even in the high range. I suppose I could have some clearance a little off, but I'm pretty sure everything was right per FSM ranges (I also put a new idler shaft in). The whine is not really noticeable around town, but above 40 mph or so it starts to become noticeable and at 70 mph it is pretty loud, definitely more present than wind noise and other powertrain sounds. Is this just life with the 4:1 kit? Input from others running these gears would be appreciated.

 

[orangefj45]

Well actually. I enquired with sumo gear themselves and they said Low Range are wrong. The high range is left standard. In the 3.1:1 kit only the idler and low range output gear are replaced so high range cannot be altered.

Are we talking about a split case or the 80/100 series HF2A case?
If it's the 80/100 case, there are gear sets available to go to 3.1:1 low range.
In these cases, low range and high range are completely independent of each other so changing the low range does not affect the high range.
Terrain Tamer also offers different gear sets for the high range, both as OD and UD sets. They're 10% higher or lower than 1:1
Georg @ Valley Hybrids & Cruiser Brothers

 

[lovetoski]

Hey guys, I just finished my LS swap and am running the 4:1 low range gear set from AA. I built the tcase myself and followed all the FSM specs, but it seems awfully noisy with gear whine even in the high range. I suppose I could have some clearance a little off, but I'm pretty sure everything was right per FSM ranges (I also put a new idler shaft in). The whine is not really noticeable around town, but above 40 mph or so it starts to become noticeable and at 70 mph it is pretty loud, definitely more present than wind noise and other powertrain sounds. Is this just life with the 4:1 kit? Input from others running these gears would be appreciated.

I have this gear-set in my 60. Installed by TorFab. I guess I have 5,000 miles on it. I have a bunch of dynomat on my truck FWIW, including all around the tranny hump. I thought the gear whine on the freeway was a little irritating at first. But I'm sure it's gotten quieter as the miles have added up. There is still a whine depending on load/coasting, but it's not too bad.

 

[workingdog]

My stock case whines like crazy. I think it's a big leap to attribute whine in high to the 4:1 gear set.

 

[scrapdaddy]

I've got the set installed by Georg, so I know it's right, but have a huge amount of gear whine at higher speeds most coming in on coasting. I never talked to Georg about it, just assumed it was normal. We travel a lot with the 55 and it does get on my nerves pretty quick, thinking about going back to a stock split case.

 

[Chuck78]

Well actually. I enquired with sumo gear themselves and they said Low Range are wrong. The high range is left standard. In the 3.1:1 kit only the idler and low range output gear are replaced so high range cannot be altered.

So would it be safe to assume that running the 3.1: 1 Low Range Sumo Gears from Georg, AA, LROR, etc, there are no changes to high range that would alter the noise vs factory gearing?

I'm trying to build a rig that cruises well on the highway for very long distances and will crawl fairly decent on mild to moderate trails.

Yes I know this is an older thread, but very pertinent information. I'm on the fence between 4.1: 1 vs 3.1:1.
I'm not trying to crawl up any crazy boulders, & have an R151F with 4.31 1st gear anyhow, & altering the overdrive ratios to .695:1 5th gear, probably will stay with 4.56's but could go with 4.88's. I think 3.1:1 will be the best all around set, especially if it will still be running on factory gears for high range.
@orangefj45 ???