Outer Limits 4x4 Board

Ooookay... since we've had all the rain, a few rather scary stopping moments have occured with Oscar (X-90 with 5in lift running 31's), that I never had a problem with when I had Stimpy (Jimny with 6.5in lift running 32's).

It's been pointed out that the brake pressure spring *may* have had to be moved to correct braking pressure under load... and be farked if i fully understand this.

Anyone else with a lifted and re-shoed Vit had these dramas?

More information please... what exactly is happening?

Even at 45km/h, if I hit the brakes it will lock up and slide - the arse end will swing/wallow as well.

It was never like this... scary stuff. A lady pulled out in front of me the other day (in the dry) and it locked up and slid... was only doing about 35kph.

In traffic if the road is even a little wet, I need to brake carefully and stay a few car lengths back. I tapped the brakes the other night to slow down as I was turning off a main road near my place and just slid through the intersection... was slowing down from only 60kph.

I've never had a 4WD do this

Shouldn't have brought an auto :p

Sounds a bit like the rears are locking up before the fronts with the arse sliding about. Perhaps an adjustable line pressure unit is needed.

sounds like mine.

yes scary in the wet and gravel.

i need to install a prop valve in mine still.

most of the braking should occur at the front , try this , get some decent brake line clamps they cost you $15 each . lock off the rear brake line and drive the car , does it stop well only on the front brakes , if poor braking still occurs you may have sticky front brake caliper slides (eg the slides may be seized , the pistons may be seized) , then with 2 clamps lock off the front brakes how does it react then?

brake fluid leaking over rear shoes will also cause a rear lockup. is 1 rear wheel locking up and not the other , do you have a seized rear wheel cylinder ,air bubbles in front brake lines ? disconnect rear propotional valve and retest ?


i believe brake proportioning should be about 60% front and 40% rear.

you can eliminate problem area by clamping off 1 brake line at a time , but do this in a place where theres no traffic .

brake problems can be a real bastard , but if you eliminate where its not a problem ,they are usually easy to fix.

Has ANYTHING been changed recently? IE: different brake pads/shoes or rear cylinders.

I think it might be a weight transfer issue that gets bigger becasue of the IFS.

Your car is fairly "soft" with the change in springs and shocks (from what I have seen) so when you are braking it would tranfer all the weight to the front wheels causing the rear to get light and either wander or lock up.

This can also cause the front to lock up as all the weight of the car is pushed foward you are then doing all the braking with the front tires which might not handle that very well.

My LWB still has all the Calmini stuff (coils ,shocks)which is supposed to be to "tight" but it will still do this under heavy braking.

You can "tighten" the suspension back up and it should be better on the road or live with it I guess.

The reason that Stimpy didnt do it was a live axle front and the ranchos is my guess.

Adjustable front struts would make all the difference but there still is not any around that I have seen.

Is your 5" lift engineered?

Any engineer who isn't drunk should have picked that up...

Squik wrote:
It's been pointed out that the brake pressure spring *may* have had to be moved to correct braking pressure under load... and be farked if i fully understand this.

OK so, they have a adjustable proportioning valve attached to the rear susp. that adjusts the rear breaking based on how much load there is in the back, or, more accurately, based on how much the rear suspension has drooped. So any suspension lift you do will necessitate moving or adjusting this valve in some manner....

HedgeBoar wrote: OK so, they have a adjustable proportioning valve attached to the rear susp. that adjusts the rear breaking based on how much load there is in the back, or, more accurately, based on how much the rear suspension has drooped. So any suspension lift you do will necessitate moving or adjusting this valve in some manner....

Except that Calmini rear A frame has a bracket for the proportioning spring on it that corrects the spring for the height in suspension lift.


I would check for correct rear brake function. The nature of Vit rear brakes are such that if the sef adjuster on one side is incorrectly installed BOTH rear brakes won't work properly, leading to excessive dive and a squirelly feeling under brakes, as brake dive winds caster out of the front end making the twitchyness worse.

Steve.

Gonzo wrote:Is your 5" lift engineered?

Any engineer who isn't drunk should have picked that up...

Yeah... it's engineered, but this is a recent issue, used to handle beautifully.

Sounds like it might be a rear end issue from what Steve said... the front end dives and the arse end flicks out. I will check the self-adjuster this weekend.
I've recently had the brakes adjusted/checked... may be the problem

Yep, sounds like someone has stuffed up rear brake reassembly.

Steve.