Outer Limits 4x4 Board

As the Title states, I'm wanting some ideas\designs to make a trac bar in the rear of my sierra for when i go SPOA, ideas would be awesome

I asked this same question months ago and got zip help or response so i went out and made my own. I used pics from magazines and designed it from there. Sorry about the rough drawing i am tired and was in a hurry. if you want some photos let me know...................By the way it works a treat

The first one I did used 3 3/4" heim joints and a shackle with the chassis mounted part at the top. The initial problem was that I kept breaking the mount off the diff housing (mounted directly over the diff pumpkin). Once I got this sorted, I found that the harshness of the heims go to be too much after a bit of wear. So I changed to a falcon trailing arm bush at the chassis end of the arm. This is rubber and it absorbs shock better so is less harsh. I am currently happy with the design. I ended up with the shackle mounted with the arm at the top of the shackle and the chassis mount at the bottom. I don't really think this make a great deal of difference. Hope this all makes sense

Pop around and have a look at the one I have under the Camolux, I'm just down the road from you at work, and across the road from where you used to work (like the cryptic location?) or I could call in to your work (still at TBS?)at your lunch break. It was Ruffs old bar - great design, very strong and the mounting position is superior in that it removes 99 percent of diff rotation without putting longitudinal compressive strain on the leaf springs. Give me a call 0413 409 006.

could ya post up some pics for us area54??

When it stops raining here I'll get under the rig and post up some pics.

i saw a range rover front radius arm used in the back of a spoa mq patrol.

nice and simple

here are some pics of one I built recently. it is made from a bundera panhard rod (solid, the bottom bar) and a 75 series tierod top), the cross brace is also from the panhard I think. the top eye is from an old patrol shock, the top eye is the original eye of the panhard rod. both have shock absorber rubbers with crush sleeves in. the chassis end has a tierod balljoint rotated 90 degrees compared to the drawings ewarlier in this thread, the "shackle"is made up from a bit of 8mm plate bent in like __/--- to align the centre of the balljoint with the centre of the vehicle. the tierod and rod end retain their threaded joint to allow a degree of adjustability. the top of the "shackle" is a heavy duty shock absorber eye and the mounting tabs on the costom crossmeber are 8mm plate; shock rubbers and crush sleeve between the "shackle" and the crossmember tabs. the crossmember is 90x5mm square RHS welded to the chassis.
the axle bracket is built up from 5 individual pieces of 6mm plate, although it could have been made up from an appropriate bit of square RHS. ramp travel is the same with/without the bar.

er. ignore this one.

i'm putting springs over the axles on a landrover and am also using a front rr radius arm mounted upside down.

modman

more pics

quick questions from an uneducated fool....

Is the sole purpose of a trac bar to prevent axle wrap?


and are there any downsides to one?

JoeLux wrote:quick questions from an uneducated fool....

Is the sole purpose of a trac bar to prevent axle wrap?


and are there any downsides to one?

Yes, needed more on a spring over type vehicle ( Hilux etc) where the springs are mounted on top of the diffs. The spring over design has more rotational leverage on the diff housing. Not needed as much on a spring under vehicle, unless the spring packs are really lightweight and super soft.

Downsides - yes if they are setup wrong, they can bind, limit travel, do more damage than needed, cause vehicle hop in shorter wheelbase rigs etc...

so all in all, if i am going to be fitting lighter weight springs and bigger tyres with lockers, a properly set up trac bar would be a good move?

Absolutely, it will make the vehicle a lot more responsive and 'trustworthy', especially when climbing. I still have the torque rod on the front to keep the front under control also - no loss of flex and keeps the front strong.

sounds like the grinder and the welder will be gettin a fair workout over the next few months... I gotta make me a trac bar... I gather yours in on the camo beast... any pics of it?

JoeLux wrote:sounds like the grinder and the welder will be gettin a fair workout over the next few months... I gotta make me a trac bar... I gather yours in on the camo beast... any pics of it?

Pics soon yes.

Has made the vehicle much stronger, climbs much better and has saved quite a few uni joints.

after i took out my spring lift (waayyyy to stiff ride) out. i noticed a huge increase in axle wrap especialy when taking off quick the rigs sooo much slower now. but flex's up heaps better

definetly my next mod!!!!

I stripped down the packs also - running a 4 leaf pack (standard length) 18mm tapered block (homemade) to correct pinion, bobbed alloy tray, 34 spare and spacecase full of spares and tools. Ride height is perfect, shocks are still in the factory position, and funny enough, on the ramp it flexes the same numbers as a lux with rears in front, IFS rears in the rear, angled shocks, new front hoops, crossover, longer shackles.

Area54 wrote:Pop around and have a look at the one I have under the Camolux, I'm just down the road from you at work, and across the road from where you used to work (like the cryptic location?) or I could call in to your work (still at TBS?)at your lunch break. It was Ruffs old bar - great design, very strong and the mounting position is superior in that it removes 99 percent of diff rotation without putting longitudinal compressive strain on the leaf springs. Give me a call 0413 409 006.

Thanks troy i'll be intrested in seeing that, nah i'm currentily unimployed due to curimstances out of my control, so let's just say that i'm looking for work and TBS are assholes , i'll call you later

Area54 wrote:I stripped down the packs also - running a 4 leaf pack (standard length) 18mm tapered block (homemade) to correct pinion, bobbed alloy tray, 34 spare and spacecase full of spares and tools. Ride height is perfect, shocks are still in the factory position, and funny enough, on the ramp it flexes the same numbers as a lux with rears in front, IFS rears in the rear, angled shocks, new front hoops, crossover, longer shackles.

Not all rigs are built to be ramp queens

Area54 wrote: funny enough, on the ramp it flexes the same numbers as a lux with rears in front, IFS rears in the rear, angled shocks, new front hoops, crossover, longer shackles.

Troy mine was this exact set up and i will put money on it that yours does not have this kind of flex.

I dont think my coil rear conversion currently has this much flex.

ramp queen

btw very impresssive

Here are a couple of pics of Troys Track bar while it was still fitted to my rig.

After running this the only prob i had was that the lower link should go as close to the end as possible. Mine was not long enough and therefore bent a little at the end so i had to weld a plate to it to fix the problem. Only reason it didnt go right to the end was i didnt have enough material at hand.

Nice pics Ruff, ... next question.....

After doing a SOA, lightening off springpaks, etc etc etc.... we obviously get an increase of diff warp under acceleration/decelleration.... a couple of months back I posted the following queery....

http://www.outerlimits4x4.com/PHP_Modul ... =vibration

for those that are too lazy to look at it ... it was in relation to drive line vibrations. Since fitting the 5spd, I now have these vibrations and they are directly related to the rear drive, I know this because ... take out the rear shaft, drive it on the front diff.... no vibes !!!

It never vibrated with the 4 spd, and has only started this since the 5spd was installed. I asume its because the transfer sits 135mm further back and there's a greater rear driveshaft angle. I have countered this by lowering the transfer case down by 25mm, which greatly improved the shaft angle and removed about 50% of the vibes.

The vibes now appear mainly when theres a change in throttle position... IE "on to off" the throttle as in gear changes and predominately at speeds greater than 80k's. The diff snout moves 20-30mm under acceleration/decelleration at a speed of 80kph and this may be causing the unis to bind momentarily and thus vibrate.

After reading this thread I'm wondering whether a track bar is the answer .

Thanks for all your ideas !!!

Troy i'll give you a call an have a lookie see under your car

Area54 wrote:and funny enough, on the ramp it flexes the same numbers as a lux with rears in front, IFS rears in the rear, angled shocks, new front hoops, crossover, longer shackles.

I've got to ask - who is this person you are referring to? And more importantly - is it me?