Jeep wrangler build

[Landy-Novice]

I absolutely cannot abide idling away my time That and I'm quite organized I have a well equipped workshop that allows me to make the best use of my time.

and then theres poor gits like me with a shed full of sh!t and a patio to work on.

great fabrication skills, cant wait for next update on this (and the gwagon!)

[Mo Murphy]

Dan, I've just read this entire thread, not that I'm in the slightest bit interested in alternative suspension set ups but just to enjoy the fabrication.

Thank you, I enjoyed that.

Mo

[dirtydiesel]

Cheers Mo, plenty more Fab work to come,

Had an afternoon on the jeep and with some help from Matt, we pulled the front axle out dialed in a little more pinion angle, protected the difflock actuator and got everything fully welded.

[dirtyninety]

Looking very smart Dan

[Anderzander]

Any more updates Dan ?

[mat wilson]

i dont think so Anderznder, hes been playing with much cooler toys

[discomark10]

Cheers Mo, plenty more Fab work to come,

Had an afternoon on the jeep and with some help from Matt, we pulled the front axle out dialed in a little more pinion angle, protected the difflock actuator and got everything fully welded.

What type of joint you using for the 1 link?

[bill van snorkle]

Off topic. Dan, unfortunately my mate inadvertently erased the photos showing how I 'bluprint' cv joints, so I will have to do it again.

Back on topic. Dan,very early in this thread you stated that you "like lots of antisquat" as one of the reasons for electing to go 'One Link'. I don't actually disagree with you as I have one link rear and my 3 link front virtually replicates the antidive/antisquat geometry of a one link front, and I am very happy with the rigs cross country capabilities.But, my vehicle is low powered and relies on a box full of gears to get the job done and doesn't have the ability to 'launch' at an obstacle.

You have built many more powerful high performance offroaders than I, and i'm interested if you would elaborate on the reasons why you prefer lots of antisquat, a position that bucks what appears to be a consenses among vehicle builders in the US, UK and here?

One question I occasionally ask myself is, Although Daimler Benz engineers are not infallible, if antisquat is so undesirable, why do they persist with one links on Unimogs and radius arms G wagons?

These are 'no expense spared' offroad vehicles built by a firm who would have no problem changing to multi link designs if they offered significant performance advantages.

[dirtydiesel]

What type of joint you using for the 1 link?

Have a read back through the thread Mark, it's been discussed in detail.

Off topic. Dan, unfortunately my mate inadvertently erased the photos showing how I 'bluprint' cv joints, so I will have to do it again.Back on topic. Dan,very early in this thread you stated that you "like lots of antisquat" as one of the reasons for electing to go 'One Link'. I don't actually disagree with you as I have one link rear and my 3 link front virtually replicates the antidive/antisquat geometry of a one link front, and I am very happy with the rigs cross country capabilities.But, my vehicle is low powered and relies on a box full of gears to get the job done and doesn't have the ability to 'launch' at an obstacle.You have built many more powerful high performance offroaders than I, and i'm interested if you would elaborate on the reasons why you prefer lots of antisquat, a position that bucks what appears to be a consenses among vehicle builders in the US, UK and here?One question I occasionally ask myself is, Although Daimler Benz engineers are not infallible, if antisquat is so undesirable, why do they persist with one links on Unimogs and radius arms G wagons?These are 'no expense spared' offroad vehicles built by a firm who would have no problem changing to multi link designs if they offered significant performance advantages.

No worries Bill, I am going with the stock cv's for now.

On the anti-squat front;

I think the huge a/s is only undesirable if there is endless grip, something we really don't have over here.

most about all my driving is in conditions of near zero grip, the extra loading of high a/s helps generate grip.

As an example my G as it was first built had above 250% a/s, it had some really unbelievable traction and worked very well but was inflexible, it would crawl well at idle as well as performing under power.

I rebuilt it on 3 link with around 130% a/s, it crawled so well I almost forgot how to use momentum, which was handy as the setup wasn't so good when hard charging, I put this mostly down to the huge amount of axle walk and the reduction in roll resistance. And my ability to tow stuck vehicles out was hugely reduced.

The terrain they build for in the us simply doesn't exist here,

I too have wondered why MB's are built like they are, and why nearly ever other manufacturer has multi link rear ends giving unbalanced systems.

My bone stock 460 swb g wagon was hands down the best all rounder I've ever had,

[discomark10]

I have, love the work, but I cant see if you said what joint you went with, you where saying about using the D2 bush (http://www.rimmerbros.co.uk/Item--i-ANR6947P) ?
I was at The land rover show last weekend and I saw a 1 link with a pin bush setup.(http://www.rimmerbros.co.uk/Item--i-STC618) not sure if it was that exact joint but seemed quite good in theory with regards to articulation.

[will4x4]

Fantastic build. Well done

[bill van snorkle]

Thanks for the reply Dan. Do you know or have you heard of anyone deleting the torque tubes on a 404 Unimog vehicle, not just Mog axles under something else, and replacing them with a link setup in an effort to improve offroad performance? I've posted a similar question on Pirate.

Bill.

[bill van snorkle]

Next i built the front 1 link, the box section i have used is 50x50x6.

The bulge in the 1 link leg is to clear the sump on full bump, i bent this in the workshop press with no formers it bent pretty well i think.

A thought just occurred to me when commenting on the Series forum, that if the link bushing was offset slightly to the left side, that torque reaction through the bushing pulling the crossmember downwards,or lifting upwards when in reverse gear, would tend to pull/lift the left side down/up a little more, thus perhaps countering propshaft torque roll which tends roll the chassis over to the right when driving forward and to the left when in reverse gear.

Unimog front torque tube spherical joints are offset slightly to the left side. Engine clearance? or to counter torque roll? Or both?

Thoughts?

[dirtydiesel]

A thought just occurred to me when commenting on the Series forum, that if the link bushing was offset slightly to the left side, that torque reaction through the bushing pulling the crossmember downwards,or lifting upwards when in reverse gear, would tend to pull/lift the left side down/up a little more, thus perhaps countering propshaft torque roll which tends roll the chassis over to the right when driving forward and to the left when in reverse gear.

Unimog front torque tube spherical joints are offset slightly to the left side. Engine clearance? or to counter torque roll? Or both?

Thoughts?

I have thought much the same Bill, the front of the 404 is offset about 9" to the left and the rear has the same amount of offset but to the right, prop shaft torque roll was not evident at all in the 404 I had.

The angle of the front torque tube is also very steep on the 404. I wonder if this has the effect of altering the torque reaction of the suspension as the angle of the torque tube would point much closer to the center of gravity than most conventional 4x4's

[bill van snorkle]

I have thought much the same Bill, the front of the 404 is offset about 9" to the left and the rear has the same amount of offset but to the right, prop shaft torque roll was not evident at all in the 404 I had. The angle of the front torque tube is also very steep on the 404. I wonder if this has the effect of altering the torque reaction of the suspension as the angle of the torque tube would point much closer to the center of gravity than most conventional 4x4's

Yes they are interesting points to ponder Dan.

I unpacked a new/reco 404 front axle from its crate tonight, and measured from swivel knuckle flange of banjo housing to each side of the pinion shaft left and right. the numbers came out at roughly 17.5" left 25.5"right, so we are looking at the torque tube swivel joint being mount around 4" to left of centre. Didn't get around to unpacking the rear end, but now that you mentioned that the rear torque tube is also offset, but to the left, suggests that something clever was going on when the designer drew that up.

Some day I might make an offset to left front One Link and scrap my current 3 link front arrangement, which due to the upper link being mounted above the diff on the r/h/side and angling down to the chassis, tends to exaggerate torque roll. Now where did I put that length of 2"x2"x1/4" RHS I bought 20 years ago?

[bill van snorkle]

Dan, you stated earlier in this thread somewhere that you previously had some success with an A frame ball joint as the one link wishbone pivot. Did you mount it with the ball pin in shear,as in vertical. or in compression/tension, as in horizontal? I do recognise that either orientation will also subject the pin to both shear and compression/tensile loadings due to antidive/antisquat and linear forces.

Bill

[Daan]

Yes they are interesting points to ponder Dan.

I unpacked a new/reco 404 front axle from its crate tonight, and measured from swivel knuckle flange of banjo housing to each side of the pinion shaft left and right. the numbers came out at roughly 17.5" left 25.5"right, so we are looking at the torque tube swivel joint being mount around 4" to left of centre. Didn't get around to unpacking the rear end, but now that you mentioned that the rear torque tube is also offset, but to the left, suggests that something clever was going on when the designer drew that up.

Some day I might make an offset to left front One Link and scrap my current 3 link front arrangement, which due to the upper link being mounted above the diff on the r/h/side and angling down to the chassis, tends to exaggerate torque roll. Now where did I put that length of 2"x2"x1/4" RHS I bought 20 years ago?

This sounds like the location helps to stop the roll under braking: the location of the torque tube does affect brake dive, as it will roll under braking. For this reason, I would not be keen to offset the central pivot. However, if you can offset the rear in such a way that you can counter act roll under braking from the front, that could be a good solution.

The location of the diff has no effect on torque roll created by the propshaft: a torque is a torque, regardless were you apply it on the axle.

Daan

[bill van snorkle]

This sounds like the location helps to stop the roll under braking: the location of the torque tube does affect brake dive, as it will roll under braking. For this reason, I would not be keen to offset the central pivot. However, if you can offset the rear in such a way that you can counter act roll under braking from the front, that could be a good solution.

The location of the diff has no effect on torque roll created by the propshaft: a torque is a torque, regardless were you apply it on the axle.

Daan

Daan, The term 'Torque Tube' can be a bit confusing to this discussion. Unimogs have torque tubes, but essentially they do the same job as Dans single wishbone links.Torque tubes have spherical joints, Wishbones have bushings or ball joints.

When driving forward in 4wd, torque reaction rolls the front/rear axle housings backwards, in the opposite direction of the wheels rotation. The front torque tube/wishbone, being rigidly attached to the axle housing, pulls in a downward direction at the chassis end. If the spherical joint/bushing at the end of the torque tube/wishbone is attached centrally between the chassis rails, it will tend to pull the chassis down squarely. If the joint/bushing is offset to the right of the suspensions roll centre, then it should pull the r/h/side chassis rail down further than the left side. But Torque reaction from the engine, transmission, propshafts also imposes a force that tends to roll the sprung mass to the right, so by off setting the torque tube joint/wishbone bushing to the left of the roll centre instead, the downforce applied by the left biased joint /bushing should cancel out the lateral torque roll from the driveline.

Well that's my theory anyway. If I had a Meccano set I might be able to prove or disprove the theory one way or the other. But I think I can make a wishbone with a bushing that can be laterally repositioned for experimental purposes.

Under brakes, in gear there should be some reverse driveline torque roll but not much so the bushing offset would not want to be too great as you pointed out.

[discomark10]

My question is, will the axel torque reaction have as much as an effect as the body torque reaction at the chassis once you account for the leverage in the 1 link arms. If not will it make a worth while difference in reducing the roll.

[Daan]

Daan, The term 'Torque Tube' can be a bit confusing to this discussion. Unimogs have torque tubes, but essentially they do the same job as Dans single wishbone links.Torque tubes have spherical joints, Wishbones have bushings or ball joints.

When driving forward in 4wd, torque reaction rolls the front/rear axle housings backwards, in the opposite direction of the wheels rotation. The front torque tube/wishbone, being rigidly attached to the axle housing, pulls in a downward direction at the chassis end. If the spherical joint/bushing at the end of the torque tube/wishbone is attached centrally between the chassis rails, it will tend to pull the chassis down squarely. If the joint/bushing is offset to the right of the suspensions roll centre, then it should pull the r/h/side chassis rail down further than the left side. But Torque reaction from the engine, transmission, propshafts also imposes a force that tends to roll the sprung mass to the right, so by off setting the torque tube joint/wishbone bushing to the left of the roll centre instead, the downforce applied by the left biased joint /bushing should cancel out the lateral torque roll from the driveline.

This bit I agree with, and I am aware of it

Under brakes, in gear there should be some reverse driveline torque roll but not much so the bushing offset would not want to be too great as you pointed out.

That is not the full story, if you engine brake, then, yes the antidive will work the other way and also cancel out bodyroll induced by propshaft torque.

However, if you slam the brakes on, a force will go upwards through the centre pivot and try to push the front of the car upwards. When this joint is offset, it will apply this force not central on the chassis, but offset, causing body roll. Considering that the brakes can create much larger forces than the drivetrain does, this would be an area of concern.

Daan

[bill van snorkle]

Sorry Daan, I wasn't implying that you didn't understand the concepts of this discussion. I tried to structure my previous post in the hope that others of less experience may understand.

I certainly agree with you about brake torque induced body roll, I get a bit of that to the left side anyway with my offset 3rd upper link. It is really only noticeable when the body settles again after the front wheels come to a complete stop, and doesn't seem to adversely vehicle control during heavy braking, even on wet sealed roads.

Due to packaging issues, I am probably only aiming for about 50mm offset at the front, and that point will be only around 50 mm below the suspensions roll centre at close to the 4 o'clock position, so not a huge amount of leverage.

Disco Mark. Depending on the conditions, driveline torque induced body roll can have a significant affect on the difference in vehicle stability left side compared to right side. The best way I had of demonstrating it, is a 'V' gully with steepish banks on one side.

With locked diffs a standard narrow tracked series L/rover can safely turn right out of the gully and drive up the bank. But turn the vehicle around and try that again by turning left, and the Landy torques over and falls its side .

Bill.

[bill van snorkle]

Well I just wasted half a day knocking up a new 'bolt on ' crossmember and half the wish bone. Whilst under my truck measuring stuff, I decided to take it for a thorough extreme cross terrain test before removing the existing 3 link arrangement.

Like most enthusiast modifyers that frequent this forum, I constantly make subtle alterations here and there to achieve a certain result , and the effect these changes have on some other aspects of the vehicles performance are sometimes not immediately noticeable. During the cross terrain test ,I was fully prepared to roll the truck over, or at least put it on its side by turning sharp left and right up almost vertical banks on the side of the tracks in order to induce severe driveline torque roll. But there was nothing !! just equal stability under all almost ridiculous situations that are rarely contemplated even when faffing around off road. !

I'm abandoning the One Link for now, and now have to go through all my previous alterations to find where the previous torque roll escaped from .

[o_teunico]

Any detailed pics of the 3link and testings?

[bill van snorkle]

Any detailed pics of the 3link and testings?

No Teunico.It was a spur of the moment decision to go for a test before stripping her down, and I had no one with me to take photos anyway. The location of my upper link, above the diff and angling down to the chassis is not one that the text books support and shouldn't work well in controlling torque roll, but it does now for whatever reason.

The only changes I have made to the truck that could have an influence on its performance yesterday was to replace the single leaf parabolic rear springs with a 4 leaf pack made from military LWB rear springs, and twin bumpstops mounted on the main leaves approx 40cm for and aft of the rear axle to give a progressive spring rate.

[o_teunico]

Is your 3rd link pararell to the other two trailing arms?