Bad front angles? You tell me.

[OT]

PICTURES HERE!!!!

Here's the deal: 7" of lift, Adj. UCAs and LCAs, D30, 33"s.

I printed off a CA length chart off here and followed the specs for my lift (LCAs=17 3/8" and UCAs=15 3/4") and the angles just looked, "off". So I called rusty's, whom I bought the springs from thinking maybe they sent me taller springs than I ordered. They said the 6.5"s are actually 7" of lift. Then I told "em what length I had set the CAs at, and he flipped out saying how that was just way to long for the LCAs. He said they should be set at 17" at the most and the UCAs should be set 1" shorter. Well, I set the lowers at 17" and left the uppers at 15 3/4" and now the angles look worse.

It looks like I should go almost 1" longer or more on both, to get the drive line to line back up and just to get the bumpstop to line up (Rusty's said to smack it with a 2x4 and a BFH to bend it so it points to the spring cup).

What do y'all think? It's trail only but I want the drive shaft and bumpstop to at least line up the way they should be.

 

[BrettM]

I think your arms are about 15 inches too short and mounted in the wrong place

as far as the bumpstops, keep in mind that when the axle compresses it will swing forward several inches, and probably hit the bumpstop. but on droop your coil is going to rub the coil tower like crazy... another problem with short arms at that height.

 

[vintagespeed]

I agree with leaving the bumpstops alone. You may want to grind the front lip off the bumpstop so it doesn't hang up on the coil during droop.

#1 - You need drop brackets. Anything over 5" should have them with short arms.

#2 - Your uppers are way too short (or your lowers are too long ), illustrated by your caster angle on the axle. You really shouldn't be worried about driveshaft angle cause there isn't anything you can do about it without cutting off your knuckles & repositioning them. Caster must be set correctly so driveshaft angles are irrelevant.

#3 - When your working on a custom front suspension you really can't listen to anyone's fixes. Especially cRusty's. You have to make the suspension work on YOUR rig, not on a ficticious model that we all see in our heads.

#4 - The only way to get your arms to work correctly is to pull the springs out & cycle the suspension fully up & down and check for issues. Do this WITH the tires on to check for front bumper clearance.

I ran 17.5" lowers & 16.something uppers before without drop brackets and it worked well for the trail but the control arm angles sucked on the street. I then added drop brackets (best mod) and the ride was better, droop was better but my tires would get into the front bumper on stuff. The moral is that you have some setup & testing to do on your custom front setup, going by "the book" or other's recommendations isn't going to work anymore.

 

[Neil]

I agree with Vintagespeed. Do what works on your rig. I have had some combinations on my rig that people said would never work. They worked on mine. Design it good, think it through, and if it works use it! Every rig reacts a little different to the same mod.

 

[RCP Phx]

Ditto on the Drop brackets or Long arms!What is holding the axle up in the pictures?

 

[OT]

Ditto on the Drop brackets or Long arms!What is holding the axle up in the pictures?

What do you mean about what's holding the axle up?

 

[RCP Phx]

It doesnt look like the tires are on the ground?

 

[OT]

It's an illusion. They're sitting firmly.

 

[XJoachim]

#2 - Your uppers are way too short (or your lowers are too long ), illustrated by your caster angle on the axle. You really shouldn't be worried about driveshaft angle cause there isn't anything you can do about it without cutting off your knuckles & repositioning them. Caster must be set correctly so driveshaft angles are irrelevant.

If you're drinving that rig on the pavement especially as a DD you will have to find a solution matching driveshaft angles versus caster. Get as much caster as possible and keep the driveshaft anglers at a point that keeps them vibe free on the highway. Vibes on the front driveshaft will destroy u-joints, differential seal and pinion bearings.

 

[OT]

If you're drinving that rig on the pavement especially as a DD you will have to find a solution matching driveshaft angles versus caster. Get as much caster as possible and keep the driveshaft anglers at a point that keeps them vibe free on the highway. Vibes on the front driveshaft will destroy u-joints, differential seal and pinion bearings.

That's kinda what I was thinking after reading all the advice. Y'know, some happy medium. But, the only pavement it'll see is in the driveway or to the trailhead.

 

[Scott Mac]

That's kinda what I was thinking after reading all the advice. Y'know, some happy medium. But, the only pavement it'll see is in the driveway or to the trailhead.

Then just set your pinion angle and don't worry about the caster. I was in the same boat. I had to chose between steerage and vibrations.
I bought a trailer and a DD and then set my pinion angle. I look silly trailering a XJ w/33s but I'm ridin' in comfort on the hwy.

 

[OT]

The problem is now you will probably need adjustable uppers to bring back some pinion angle and driveshaft length.It you check you will probably find that youre way over on castor!

they're adjustable uppers. I was gonna adjust out the UCAs and do like Vintage said and cycle it without the coils in. I'll get the pinion angle as in line as possible. However I guess I need to find some drop brackets.

 

[XJBill]

I used the same chart when I lifted my XJ to 6.5". The chart is wrong on the UCA's. They should be longer at least a 1/2" from what the chart says. Rusty's is right, the uppers should be no more than 1" shorter than the lowers. I picked up front vibes because of going by the chart. I went with the 17" on the lowers and 15 1/2" on the uppers from the chart. I finally ended up going about 16" to 16 1/4" on the uppers to get rid of vibes. Also, look at your lower shock mount, it should be horizontal. Not angled down in the back. Don't worry about the bumpstop lining up with the axle, it will when you stuff. Everthing moves forward when you compress the coils.

 

[XJBill]

I just noticed something else from looking at the chart again. Do you notice how the length of the LCA goes up faster than the length of the UCA from stock? I would think they would increase the same keeping the same length ratio. Which is how it ended up for me in the end.

 

[OT]

I just noticed something else from looking at the chart again. Do you notice how the length of the LCA goes up faster than the length of the UCA from stock? I would think they would increase the same keeping the same length ratio. Which is how it ended up for me in the end.

Yeah, I just figured the change in difference was due to the fact that the uppers stay closer than the lowers to the axle.

Thanks for your pointers. I'll try the shock mount thing. Guess I'll just grind the lip off the bumpstop to try and smooth thins out.

 

[vintagespeed]

Then just set your pinion angle and don't worry about the caster. I was in the same boat. I had to chose between steerage and vibrations.
I bought a trailer and a DD and then set my pinion angle. I look silly trailering a XJ w/33s but I'm ridin' in comfort on the hwy.

Dont worry about the caster? Huh? Caster is the only thing to worry about if this rig ever touches highway to get to the trail.

Might as well say, dont worry about pinion bearings, tire wear, steering joints & death wobble.