Wheel Travel

[Talik]

Does anyone know what the wheel travel is for stock, 4" lift, and 6" lift? The bronco in question is a 92 with the TTB and I currently have no lift, but am deciding which one to get to improve my travel for rock crawling. I'd also be interested in how much travel I'd get out of switching to a solid front axle.

Thanks.

 

[Justshootme84]

Very good question!!! While I haven't seen any specific numbers, I can tell you what limits wheel travel on the TTB (Twin traction Beam) axle. The stock radius arms are quite short, so the option of extended arms (14"-15" more) in a lift kit will improve wheel travel along with the longer coil springs. Removing the anti-sway bars alone also helps. But a solid/ straight axle suspension has more wheel travel than the TTB and is better-suited dfor rock crawling. The biggest factor to consider is really tire size, since the TTB cannot handle large tires verey well in my opinon. JSM84

 

[Roadkill]

I'm not sure of the exact amount of travel, but there is very little difference in wheel travel between a standard 4", 6" or stock ttb. Reason being is that when the lift goes in you move all the mounting points straight down, so the limited geometry of the TTB isn't really changed. (it's just moved a few inches lower) The best way to increase wheel travel is to use extended radius arms with wichever lift you choose. That moves the pivot point for the radius arms further back on the frame and the longer arm provides a larger travel arc. Even then, travel of the TTB is very limited when compared to a solid axle, but the solid axle costs much more to do. But, as far as independent suspensions go however, the TTB is much better than the upper and lower control arms used by all the truck manufacturers of today.

Here are a few pictures of my truck (6" inch lift, extended radius arms) on an RTI ramp and some video of its wheel travel.

 

[Roadkill]

JSM84 makes a good point about the tire size. The bigger, the better for rock crawling. But I did this (see video) with just 35 inch tires.



It probably wouln't have snapped if the front was not locked, but then without the locker, I wouldn't have made it to point where it broke. Catch 22 /emoticons/[email protected] 2x" width="20" height="20" />

 

[Miss Kitten]

one of the biggest things that i've learned is that front end travel is good, but you have to make sure that you have the correct leaf springs in the rear. my front end moves just fine (with the ttb) but it's the rear that i keep lifting tires on

getting rid of the sway bars is the best idea, and the extended ra's are a must for travel

 

[shift1313]

if you want a lot of travel look into the baja guys trucks. fantelli motorsports i think it is. and fabtech. i want to say 13" of travel up front for high speed driving

The best bet to get a lot of travel out of ttb is custom extended arms and widening the wheelbase. but you will always run into axle clearance issues inside the arms!

 

[Justshootme84]

Yes, if you look at Autofab's wensite, Ithink they claim 14-15 inches of wheel trav el with their custom-bent TTB beams. Many of the 4" or 6" lift kits have shocks with 14" of travel, so I'd say that's the limit or the max amount you can encounter. my shcosk on the Dana60 SAS have 14" of wheel travel, but I have limiting sgtraps so they don't bottom out or over-extend. Anytime you can get 8-10" travel on both sides, you're doing well for rock crawling with 36-38" tall tires. That's the real killer, even on a Dana44 solid axle like my 78 Bronco has.

If you can let us know what size tire you're looking to run and how hard you want to push the Bronco, we can provide you some more specific info. Both Roadkill and recently pushed our broncos to the breaking point on a big rock crawling event, JSM84

 

[Talik]

Thanks for all of the great responses.

I have a set of 35"x 14.5 tires that are currently on the bronco. (with no lift. I know, crazy, eh?) I'm going for a good all around off-road vehicle that has a balance between speed over moderately rough terrain (baha style) and slow rock crawl over very rough terrain. I'm trying to keep the CG as low as possible for handling at higher speeds but I understand the necessity of getting some more wheel travel. I like the idea of TTB over solid axle for a little more control at higher speeds (and doesn't that give you more clearance since the diff can be higher compared to the center of the wheel?). It seems like the two main things that are holding me back right now when I take it out to the trails is travel and my stock non-locking diffs. The sway bars are already gone.

It's sounding like maybe I should go with the 4" lift with the extended radius arms.

something like http://broncograveyard.com/bronco/i-33719_..._arms_90-96.htm or http://broncograveyard.com/bronco/i-33720_...dius_arms_9.htm

From what I can tell, the difference between those two is that one gives you an extra leaf that you add to your existing rear end and the other completely replaces your leaf springs? Is there an advantage to completely replacing?

I'd also be interested in hearing some recommendations for locking diffs to think about or anything else that might help me.

 

[shift1313]

i think replacing the entire leaf pack is always better than add-a-leaf. if you go add-a-leaf remove the bottom leaf from your stack and replace it with the more arched leaves. I think you will get better suspension characteristics from a correctly sized leaf pack.

look up rodd fantelli or fantelli motorsports and check out some of their fords. They do baja high speed trucks.

what truck do you have? year, engine, tranny etc. I dont have any first hand experience with lockers on these trucks so i dont know an answer for you. I dont think there is a bad locker out there though. I think your biggest choice will be manual or air powered engagement.

 

[shift1313]

oh and i read some of rodds trucks have 22-24" of travel up front, but you are getting pretty serious in the fab work for that.

 

[Justshootme84]

As pointed out, the rearend with leaf springs is often flexxed tothe max before the front. For that reason, a new lifted spring pack is better than the stock leafs with an AAL or blocks. You'll gain more travel thru a shackle flip on the rear springs, which will give you 4-5" lift using the stock springs. that's what I'[ve done on the 84 Bronco and it made a noticeable difference right away.

I do agree that for fast washboard dirt driving, the TTB seems to handle better than a solid axle. However, the limits of thew TTB in tire size, travel and alignment are more than offset with a solid axle, IMO.

Roadkill has ARB lockers front & rear and I think that's the ultimate for selectable lockers. I'm more of a spool guy, since I don't drive on the roads. Any type of traction aide is going to stress the axleshafts hardere than an open differential. And that's been the deciding factor for me in going with a Dana60 for 36" tires on the 84 Bronco. JSM84

 

[Talik]

It's a '92 with the 351w, an automatic tranny and the push button 4wd and low. I'm not sure which diffs it has but I believe everything is stock. I do need to be able to drive on the roads a bit since I don't want to tow to the trails and there aren't any trails near my home, but it's not a daily driver so I don't care about performance on the roads so much. It takes about a 45 minute highway drive to get to any good trails though.

We're looking for manual lockers.

How hard is it to modify the TTB for more travel? We're ok with a bit of fab work.

 

[BB33's]

I think you were on the right track with the 4" and 35's. 4 inches will clear 35's and keep the cg low for spirited driving. If you want more room out of the 4" cut out flares are a good option but costly. Most guys cut the fenders then roll the edges to make it look stock. As far as travel the kit you purchase reallynneeds the extended arms, like everyone else mentioned the longer arms moves the suspension pivot point back and increases travel. As far as lockers a tried and true combo for TTB is a Detroit locker in back and a trutrac in front. The stock rears are good but they really need a beefing to handle 35's well, I used the Superior axle super 8.8 kit, it includes new alloy axleshafts and they are 31 spline, they claim a 29% strength increase over stock.