handling completely altered by rear & bull bar.....normal?

[snowman]

Logic tells me that the firmer your suspension is on-road, the less travel you're likely to get & more uncomfortable the ride is going to be on a rough track, especially with corregations.[/b]

the best thing you can do on corrugated dirt roads is let your tyres down from highway pressures to low-mid 20's (depending on how bad / fast it is). you wont believe the difference it makes.

[trouble]

^^^^that too^^^^

[sydneymark]

I've left the tyre pressures at standard road pressure (40psi) for the past few weeks of dirt road driving and it's been habdling just fine.

[AussieAnth]

AussieAnth, did you get a chance to check the vehicle heights now compared to when it was first installed? It sounds like when the suspension was fitted, it was sitting too high in the front. This can make the ride very firm if the upper-control arm is hard up against it's droop stop. Once the weight of the bull-bar was added, it would have dropped a bit (up to 15mm depending on coil strength and bull-bar used). This can take the UCA off the droop-stop, allowing the front suspension to move much more freely.

Ok, I measured up the Triton last night. If I didn't take the measurements right, let me know how and I'll re-do it tonight.

Distance from centre of wheel hub to the bottom of the wheel arch is 60cm. Road to wheel arch is 94cm (factory 16" wheels/tyres). Variances on all 4 wheels were within 10mm at most, but closer to 5mm.

I didn't take a pre-EFS install or pre-bar work install measurement. I do recall my EFS installer saying the front came up 3" and rear 2", which was before the bull & rear bar. The front springs are Heavy Duty units intended for bullbar & winch, hence the extra 1" pre-bull bar.

I've read that there have been variances in the factory ride height of the MN by as much as 2.5 cm since they came out. Mines manufactured in Sept 13.

[snowman]

take a photo of the front wishbone clearance to the bumpstop (the bumpstop that hits when suspension is fully extended - not compressed).

[viking shippy]

I've left the tyre pressures at standard road pressure (40psi) for the past few weeks of dirt road driving and it's been habdling just fine.

Well graded roads yeh.....but anything with coronations I'm down to 30psi above 80ks
I always observe the rule under 30psi under 80ks.

[AussieAnth]

take a photo of the front wishbone clearance to the bumpstop (the bumpstop that hits when suspension is fully extended - not compressed).

I think this should be a good shot.

The Triton is in the driveway on moderate uphill gradient, but I dont know if it matters for this photo.

[har05l]

I think that pic may be your answer, your riding on the bump stops so in this have no travel or front end play, in other words you need to lower the front with different coils.

In comparison this is mine


I'd also be a little concerned about the cv angle , again you can see the angle mine are

[hvac guy]

Hom many mm gap is that haro

[biggibbo]

What he said-it's too high and riding on the upper bump stop. No wonder it's handling like crap

[AussieAnth]

I think that pic may be your answer, your riding on the bump stops so in this have no travel or front end play, in other words you need to lower the front with different coils.

In comparison this is mine


I'd also be a little concerned about the cv angle , again you can see the angle mine are

Thanks. I'll take the photo again on flat ground and re post if it looks different.

[snowman]

it doesn't look like it is touching, it looks like it is mashed onto it.

way too high!

[al coholic]

No offence intended mate but I'd be asking serious questions of your so called "4x4 mechanic" to hand the vehicle back to you in that condition

Surely he has worked on IFS vehicles before?? If a bunch of blokes can diagnose a firm bouncy ride over the internet and all he can advise is to get a mouth guard to stop your teeth chattering, doesn't say much about his abilities to work on 4x4's

Just sayin'

[Cowboy Dave]

The thing that strikes me as odd about all of this is the deterioration between the springs being put in and then the barwork being added. Am I missing something there?

[DocBassett]

Thats what is confusing me dave.... if it's too high, wouldn't it have been made worse before the barwork and slightly better once the bar work is added?
Perhaps the rear end is sitting even/lower than the front now giving a horrible ride/steering?

[Cowboy Dave]

Like a leverage thing with a low rear lifting the front? Kind of makes sense especially since we know the rear should be higher than the front. Still something missing from the picture for me.

[DocBassett]

Like a leverage thing with a low rear lifting the front? Kind of makes sense especially since we know the rear should be higher than the front. Still something missing from the picture for me.

Exactly. If the front is really that high, there would have to be a 3 inch or so lift in the back to make it sit the way it should. If the rear wasnt lifted the same amount as front, then the steering would be terrible, and a possible cause- well a contributor anyway. ... the front still needs to be lowered.

[Rd1]

Could they have installed a strut spacer thinking the bull bar was going to make the front sag?

[har05l]

Hom many mm gap is that haro

You do mean between the upper bump stop don't you , if so it's around 7mm

Distance from centre of wheel hub to the bottom of the wheel arch is 60cm. Road to wheel arch is 94cm (factory 16" wheels/tyres). Variances on all 4 wheels were within 10mm at most, but closer to 5mm.

I didn't take a pre-EFS install or pre-bar work install measurement. I do recall my EFS installer saying the front came up 3" and rear 2", which was before the bull & rear bar. The front springs are Heavy Duty units intended for bullbar & winch, hence the extra 1" pre-bull bar.

I measured my front and from centre rim to guard I got 575mm AA so I think the installer has over anticipated your front end weight with fitting the heavy duty coils.

Can you now measure the rear the same way, I have around 610mm

I think regardless you need to lower the front with a softer coil

[AussieAnth]

Might have found something that explains it. I had a quick check on the EFS website. The following PDF lists all the MN suspension parts
[url]
http://www.efs4wd.com.au/Online%20Catal ... shi/25.pdf[/url]

I'm using the Elite series shock absorbers on all corners, and 150kg constant load rear leaf springs.
I discussed this with him when I placed the order, and the HD/150kg constant load setup seemed to be the best choice for adding bar work & winch soon after, and suiting the rig primarily a camper/tourer, so I don't fault the choice of parts.

I've got the MIT-109HE coils (its even printed on the springs) which are described as
"75-100kg load bearing accessories" where as the standard ones listed above it are "up to 65kg" load bearing accessories"

So my bull bar was probably only 50kg with brackets. So maybe when I add a 35kg winch, which will push it up to 75kg+, the extra weight will settle the suspension lower, and it wont rest on the bump stops any more? IE: I'll have 75kg+ on the front, thus matching the coils designed for 75kg plus. Sound logical?

With all the HD springs & extra load leafs, but no extra weight to settle it down, I can understand why it was so firm, especially if it was resting on the top bump stops up front. My mechanic suggested I probably need a little more weight in the back to settle it, as he thought it was rebounding quickly and giving a little bounce, so I'll see if I can somehow safely hang some extra weight on the front, and an extra 50kg-100kg in the back, and take it for another drive.

Have other MN owners opted for heavy duty coils & leaf springs to handle bar work and a load in the back? I guess its brand specific to your choice of suspension & design.

I'd love to better understand the setup on a rig that can drive like its on rails and still be comfortable at speed on rough roads, like many members suggest they have.

[Cowboy Dave]

I've got the setup but I won't pretend to understand it. I just took it to the place, told them what I do with it and said it mustn't go higher than 1.9m at the highest point and they set it up for me. I had to go back after the bar and winch went on and then again when the rear drawers went in just for some fine tuning to account for the extra weight.

Do you have the winch yet? They are certainly pretty bloody heavy and they're way out front so you get maximum leverage there. Cable will be way heavier than rope too if you're choosing. Another great source of front weight is a second battery but you wouldn't want to have to pay for all of that just for ballast purposes.

Weight in the back does make a big difference in the rear. You often hear on the forum of blokes who had them riding a bit skittish and then settling down with some weight back there. A couple of bags of cement, or sand, or pool salt (just don't let salt go everywhere...) or maybe some containers full of water or a heavy toolbox - depends what sort of stuff you have access to as to what's best to try.

[oldplodder]

Aussie A,

Have you considered the sloppy handling you are finding are more than just springs? Shock setup makes a difference too. Also the progression in the springs, how fast do they load up?
e.g. you can go for the rally type setup which is softer more progressive setup, or a stiffer road setup, and anywhere in between.
I know, suspension theory is that basically shocks are meant to control springs, but there are adjustments you can make in design of the valving to fine tune the suspension.
So did you talk through the type of driving and comfort levels you want before buying the suspension and not just talk springs and static loads?

[AussieAnth]

No winch yet.

I just stuck about 30kg of gear on the front, and found about a 3mm gap has now appeared from the bump stop. That's on flat ground too. Was still touching without the extra weight.

I can't think of anything heavy and small enough I can safely secure to the front and then go for a test drive.

[borngeek]

do you own a child? they can be secured with zip ties. sometimes need duct tape if they get noisy.

[Cowboy Dave]

Ratchet strap. I'll lend you one with the kid...