4 to 1

[ipkyss]

an end to everyones problem, that has tons of money...

 

[Goatman]

just looking for some info on the tera 4:1. I need more gear. Not sure what way to go. How long have you had it, have you broke it, ect.

I've had a Tera 4 to 1 for over 6 years, and I'm very glad to have it. I have an automatic, and currently have 5.13's and 37's, but I ran it with 35's and with 4.56's and 33's. I calculated the gear ratios before I got it, and it pretty much adds one lower gear to the tranny's ratios. What happens is that 4th becomes like 3rd, 3rd becomes like 2nd, 2nd like 1st, and you get a new lower gear. So, if you want to know how it would be in low range with the 4 to 1, just don't use OD when you're in low range, and that will be what it's like (except for the new real low 1st).

The 4 to 1 let's you have more control while crawling, and makes it more comfortable to run rough trails and boulder fields, since you don't need to give it gas to get up the small and medium sized rocks and then brake to come down, you can just drive over them. You end up using less throttle and less brake while running trails. Low t-case gears are for rocks, if you run mud you don't need them. It's a little silly to hear a guy say that they didn't like the 4 to 1 gears in the mud, or you couldn't go fast enough on dirt trails.......no kidding, why do you even have them?

The Tera 4 to 1 does have an Achilles heal. It can't handle speeds over 3000 rpm in high gear (2200 rpm in OD), so you have to limit your speed sometimes in low range, or just shift into high range if you're going to run quicker through a section of trail (please don't do the crawl through every situation on the trail like some of the Toyota guys are known to do). The weakness is the pins that hold the small pinion gears in the planetary housing. They are staked to hold them in the case, which is using a punch to make indentations around the edges of the holes in the case to hold the pinion pins in place. Mine broke one time (and I wasn't paying attention to over revving it), and one of those pins came out of the case and broke. I heard through a friend, that was using a 4 to 1 in competition, that Tera recommended putting a tack weld on the ends of those pins to hold them in the case better, so I did that and haven't had any problems with mine in the five years since doing that.

Regarding the Klune V. If you have an ealier model XJ with a 21 spline input shaft in the t-case, the extra torque of the Klune can break the t-case input shaft. Just think about 4 times the torque going into the t-case. It's a nice idea, but in most cases the 4 to 1 will easily get the job done. The Tera kit does come with a whole new front case half, which is much beefier and is a very good upgrade for the NP231 t-case. You don't get that beefier case with the Klune V, so the extra torque from the Klune is going to go through a stock T-case housing. If you have a stick, the combined low gears of both the Klune and the t-case might be a good thing, but be sure to use a 23 spline t-case input shaft. If you have an automatic there is no use whatsover for the extra low gearing.

 

[FELIX]

The Tera 4 to 1 does have an Achilles heal. It can't handle speeds over 3000 rpm in high gear (2200 rpm in OD), so you have to limit your speed sometimes in low range, or just shift into high range if you're going to run quicker through a section of trail The weakness is the pins that hold the small pinion gears in the planetary housing. They are staked to hold them in the case, which is using a punch to make indentations around the edges of the holes in the case to hold the pinion pins in place. .

I put my Tera in at the end of last year, & the Pins were all welded in, so I think they've improved. They still do not recomend long durations in RPM's over 3000, & use hi instead of low 4th or 5th. Like stated they are made to slow you down & give better contol. For me if I need to shift to 4th in low, 1st high easily covers it. Been happy w/ mine no problems

Rob

 

[DrMoab]

an end to everyones problem, that has tons of money...

So they are 2800 bucks. Whats an atlas? 2K? and a klune is 1700 bucks. So you chould have the same thing and atlas and a klune would give you for 900 bucks less...Sounds good to me.

Now I just need to go rob that bank.

 

[FELIX]

So they are 2800 bucks. Whats an atlas? 2K? and a klune is 1700 bucks. So you chould have the same thing and atlas and a klune would give you for 900 bucks less...Sounds good to me.

Now I just need to go rob that bank.

Actually no. A Klune works in conjunction w/ a Tcase. You can engage the tcase in low 2.72 example, & also add the Klune 4.1 on top of that for roughly 10.9 reduction before R&P gears come into play. You can also just engage the Klune by itself, of the Tcase by itself. The stack has no multiplier that I'm aware of. You have a choice of either 5.44 or 3.05, but can't combine them like a Klune.

Rob

 

[DrMoab]

Actually no. A Klune works in conjunction w/ a Tcase. You can engage the tcase in low 2.72 example, & also add the Klune 4.1 on top of that for roughly 10.9 reduction before R&P gears come into play. You can also just engage the Klune by itself, of the Tcase by itself. The stack has no multiplier that I'm aware of. You have a choice of either 5.44 or 3.05, but can't combine them like a Klune.

Rob

Yeah I know..The advantage of a Klune is to give you another set of gears. So you have hi range, low range and low low range.(actually I guess you get another too)
That Stacker gives you three sets of gears. Hi,low and low low...To me thats the best option. One case and good super crawly gears and good regular low range gears too.

 

[FELIX]

Stacker gives you three sets of gears. Hi,low and low low...To me thats the best option. One case and good super crawly gears and good regular low range gears too.

Yep I would have to agree, but I live on a real world budget, so the Tera works great for me.

Rob :sunshine:

 

[RCP Phx]

Where did you get the roc trac?and how much?

I bought it new from Jb Conversions,$1800!

 

[ipkyss]

I don't normally go past 3rd low anyways. So i should be fine. If i am going fast enough to run 3rd low, i don't want to be in 4 wheel anyways, so i go to 2 hi.