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nattybumppo
06-12-2011, 11:22 AM
It has become apparent that a gearing change would be helpful in my 40, but I don't want to sacrifice speed (I know, what's that? when in a 40) on the highway. I want to be able to crawl along nice and slow when in low range and first gear. What do you 40 guys like?

Dr. Schlegs
06-12-2011, 11:50 AM
What are you currently geared at and what tire size are you running? Plus how much on-road vs. off-road are we talking?

FJBRADY
06-12-2011, 12:43 PM
Orion 4:1 :D

If your running 33's....4.56. 35's 4:88's

Search for a crawl ratio calculator on line and you can add and subtract tire sizes, t-cases, transmissions, gears,etc.

I have the SM420, Orion 4:1, and 4:10's running 36's.
Randy has a toyota 5 speed, H42 (I think), Orion 4:1, 4:88's and 37's

Your probabaly 45:1 stock.....If you can double it and still keep it streetable I think you will be very happy with it!

Good luck!

Air Randy
06-20-2011, 02:50 PM
Sascha,

Is the gear ratio and tire size you currently have OK when driving on the street? When climbing uphill on the highway?

If not, then your first move may be to chage the axle gear ratios, especially if you think you will go to larger tires.

If so, and if you aren't planning to go with larger tires, then you're probably better off keeping your diff gears the way they are.

You then have a couple options. You can either change the TC ratio or your transmission.

As far as trannys I personally don't recommend going to an SM420 simply because you end up using adapters and such, modifying cross members, etc. They work really well but it's a fair amount of work and you can have maintenance issues. You can achieve almost the same reduction in your first gear by getting a Toyota H41 4 speed. You can get those from SOR or Mark's Offroad for about $600, maybe cheaper if you hunt for them on MUD but they sell really fast. The nice thing about the H41 is it's a straight bolt on with no mods required. Just make sure you get one with the right spline count for your TC. The good thing about an H41 or SM420 is they give you a really low crawler gear especially when off road. The bad thing about them, when driving on the street in high range, it's almost like you've gone from a 4 speed to a 3 speed. In the Mule, the H41 1st gear is so low I just start off in 2nd gear most of the time, thus the comparison to a 3 speed.

For keeping all of the on road driving manners exactly the same as it is today, but to give you the ultimate crawler gearing in low range, go with the Orion transfer case. It's the priciest option as the kit is around $1700. You then remove your old transfer case, install the input shaft from your old TC to the new one and reassemble it.

RLMS
06-20-2011, 03:03 PM
Even if you stick with the h42, the orion is the way to go. Then if you feel that you don't have enough low range in first you can swap a h41 in later down the road!

On a side note with the orion, twin stick it 250$, get a NIB main shaft195$, high low clutch gear 55$ and a nose cone saver45$ If you don't the orions like to pop out of gear. And yes there are some people with no issues, but thats not to say your won't.

Justin

nattybumppo
06-25-2011, 08:29 AM
Even if you stick with the h42, the orion is the way to go. Then if you feel that you don't have enough low range in first you can swap a h41 in later down the road!

On a side note with the orion, twin stick it 250$, get a NIB main shaft195$, high low clutch gear 55$ and a nose cone saver45$ If you don't the orions like to pop out of gear. And yes there are some people with no issues, but thats not to say your won't.

Justin

Justin, Is the "NIB main shaft" the splined shaft that goes through the tranny and into the TC? If so that is a great idea since mine is pretty worn where the gear in the TC hit it.

Thanks for the info guys!

CBone
06-25-2011, 11:13 AM
Sascha,
I know we've spoken a lot about this. This chart is a great way to see the variables and how it will all play out (at least from an RPM and speed perspective): http://www.grimmjeeper.com/gears.html