Offroad Trailblazers and Envoys

<REAL TB> Feedback on 33" Gear Ratio

G80, GU6, GT4, GT5, WTF? This section is for gearing and driveline stuff.

3.42, 3.73, 4.10

Factory
0
No votes
3.42
1
8%
3.73
3
25%
4.10
4
33%
4.56
4
33%
 
Total votes : 12

by The Roadie » Fri Mar 16, 2012 3:15 am

Depends on what trails you want to go on. Research the trails and talk to folks who go on them and LOOK AT THEIR TIRES. All of the places I go would tear up 20's with such little sidewall. ESPECIALLY when aired down. Then the rims get dented.

Research the trails. Talk to folks. Get out there. Don't think you can learn it all on the net.

11" wide is also HUGE to me, but I appreciate side lugs that those sorts of tires don't come with. And a higher load range. And lots of plies in the sidewall. There is also a school of thought that tall skinny-ass tires are better for certain conditions, like 255/85-16.

Picking the "best" tires requires you to articulate what sort of offroading you want to do, and I don't think you've done enough yet to know. After a year or two, MY desires change and I need new tires anyway, so it's an evolution.
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by DavidRant0n » Fri Mar 16, 2012 3:32 am

I have moved past the 20s lmao! What do you think about the Z71 Wheels!?
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by Nakashige » Fri Mar 16, 2012 7:51 am

You need wheel adapters to go from 6x5 to 6x5.5 go see mark for them
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by navigator » Fri Mar 16, 2012 8:18 am

everybody knows to be a real offroader you need 15 or 16 inch steel rims painted black with no lug nut covers!


all jokes aside, with 20 inch rims you have a much shorter sidewall, the edge of your rim is closer to contact with rocks and debris. For offroading the maximum sidewall available is desired.

Think about that tire sitting on pavement your tire is 11 inches wide but maybe only has 2-3 inches front to rear contact with the pavement.
Depending on how much you air down you increase that to 4-6 inches or more. You are increasing your traction by double or triple.
On rocks you would see a similar effect and an aired down tire has grabs things better than a tight tire.

In sand or dirt the contact path increases even more.

By going with a 20 inch rim you limit your ability to air down effectively, get your rim closer contacting things and are more likely to pop a bead if you air down.

I think the rule of thumb is you want at least as much sidewall as rim height.
If you are running 35's you might be ok with 18 inch rims. If you are running 33's, you want to stick to a 16 or 17 at most.

think about it, next time you are running in that creek bed do you want to be able to crawl out or get pulled out?
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by DavidRant0n » Fri Mar 16, 2012 2:20 pm

navigator wrote:everybody knows to be a real offroader you need 15 or 16 inch steel rims painted black with no lug nut covers!


all jokes aside, with 20 inch rims you have a much shorter sidewall, the edge of your rim is closer to contact with rocks and debris. For offroading the maximum sidewall available is desired.

Think about that tire sitting on pavement your tire is 11 inches wide but maybe only has 2-3 inches front to rear contact with the pavement.
Depending on how much you air down you increase that to 4-6 inches or more. You are increasing your traction by double or triple.
On rocks you would see a similar effect and an aired down tire has grabs things better than a tight tire.

In sand or dirt the contact path increases even more.

By going with a 20 inch rim you limit your ability to air down effectively, get your rim closer contacting things and are more likely to pop a bead if you air down.

I think the rule of thumb is you want at least as much sidewall as rim height.
If you are running 35's you might be ok with 18 inch rims. If you are running 33's, you want to stick to a 16 or 17 at most.

think about it, next time you are running in that creek bed do you want to be able to crawl out or get pulled out?



I will be running either my stock 16" or the Z71 16" on 33s
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by djthumper » Fri Mar 16, 2012 3:42 pm

DavidRant0n wrote:
navigator wrote:everybody knows to be a real offroader you need 15 or 16 inch steel rims painted black with no lug nut covers!


all jokes aside, with 20 inch rims you have a much shorter sidewall, the edge of your rim is closer to contact with rocks and debris. For offroading the maximum sidewall available is desired.

Think about that tire sitting on pavement your tire is 11 inches wide but maybe only has 2-3 inches front to rear contact with the pavement.
Depending on how much you air down you increase that to 4-6 inches or more. You are increasing your traction by double or triple.
On rocks you would see a similar effect and an aired down tire has grabs things better than a tight tire.

In sand or dirt the contact path increases even more.

By going with a 20 inch rim you limit your ability to air down effectively, get your rim closer contacting things and are more likely to pop a bead if you air down.

I think the rule of thumb is you want at least as much sidewall as rim height.
If you are running 35's you might be ok with 18 inch rims. If you are running 33's, you want to stick to a 16 or 17 at most.

think about it, next time you are running in that creek bed do you want to be able to crawl out or get pulled out?



I will be running either my stock 16" or the Z71 16" on 33s

So what gear ratio do you have now? If you only have 3.42s do you plan on upgrading to at least 3.73s?
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by DavidRant0n » Fri Mar 16, 2012 11:45 pm

I still haven't checked... Whatever I have I intend to step down 1.... 3.42 - 3.73 - 4.10 - 4.56
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by The Roadie » Sat Mar 17, 2012 7:49 am

DavidRant0n wrote:I still haven't checked...
For pete's sake WHY NOT?!?!?!?! Takes 30 seconds?

And as I posted before, it's a silly misuse of your funds to be changing gears until you prove you need them by wheeling it hard and running into the limitations of what you have. You already have a low range transfer case, and for extra credit, find and tell us what that ratio is. You should already know that if you're ready for this project.

To wheel it hard, you need armor a lot earlier than you need gears. And you need to find buddies you can trust to wheel with on LEGAL trails. And you need to invest in recovery and survival gear.

Until you can find the gear ratio of your transfer case's low range, I'm done with this thread.
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by NC_IslandRunner » Sat Mar 17, 2012 12:05 pm

And a good basic guide for tire to wheel for offroading is the tire should be about double the wheel size I.E. 16" wheels need close to a 32" tire.
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by Trail X » Mon Mar 19, 2012 9:09 am

The Roadie wrote:And as I posted before, it's a silly misuse of your funds to be changing gears until ...


Maybe he has a money tree?
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by v7guy » Mon Mar 26, 2012 11:54 pm

I'm with these other guys. I've got a spare front diff sitting in the garage and I still haven't bothered with gears... mostly cause I'm still working on this abortion of a rad skid, but still. Get some armor and recovery gear first. Then worry about how to help the vehicle not get stuck in the first place.
P. S. 20s aren't going to be too great on a trail.
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