Grande Airbag Retaining after a Lift

[1coolbanana]

Mine started out a little different at 790-795 and 11mm gave me 825 on the left.
Both side were not the same, right side was a little lower and took 14mm to achieve the same thing.
Ive found that from day to day it can vary by 10mm, is anybody elses like that?

[craigm]

Peter, Is this where you have left the rear? i.e. with the 16.5mm spacers? or was this exercise purely in the name of science?

[1coolbanana]

A very good point there Marc, but what I was getting at is that I haven't heard of airbags popping unless some extreme articulation was involved. Also the chances of popping an airbag increases dramatically if you install longer shocks. If you choose a shock with an extended length that is not too much longer than the standard shock, and keep enough droop to stop the shock from topping out, then you shouldn't have any dramas. I think the Bilstein at 580mm extended, compared to 575mm extended for the standard shock is a good compromise here.

Yep, understood and agree completely.

[Peterpilot]

I also did some experimenting a while ago with some spacers. I found that with 16.5mm spacers, a lift of 50mm was achieved. This was from 780mm to 830mm at normal height setting:



I then jacked the suspension to the high setting:



and measured the ride height at 865mm:





With such little droop left in the shock at this height, use with caution or in emergencies only.

As far as the spacers are concerned, I found that the ratio of spacers to ride height change was almost exactly 3.

[Peterpilot]

945 at the wheel doesnt necessarily mean the shock extends any further as the pivot point is around the lower shock mount. The wheel is outboard and the airbag is inboard so the airbaig wont be extending any more with the opposite wheel at full compression, as the angle increases, the extended airbag may well be "less" extended.

A very good point there Marc, but what I was getting at is that I haven't heard of airbags popping unless some extreme articulation was involved. Also the chances of popping an airbag increases dramatically if you install longer shocks. If you choose a shock with an extended length that is not too much longer than the standard shock, and keep enough droop to stop the shock from topping out, then you shouldn't have any dramas. I think the Bilstein at 580mm extended, compared to 575mm extended for the standard shock is a good compromise here.

[1coolbanana]

Oooohhhhh Senior member now... do you feel any more special??? ha ha ha.

ha ha, yeah, for a couple nano seconds

[craigm]

Oooohhhhh Senior member now... do you feel any more special??? ha ha ha.

[1coolbanana]

Agreed that it minimizes your down travel, but I would'nt be disabling the switch. There will always be times when you may need that extra 40mm to save you from damaging the rear end of the Prado.

Yeah ok, maybe not disable it

[craigm]

Agreed that it minimizes your down travel, but I would'nt be disabling the switch. There will always be times when you may need that extra 40mm to save you from damaging the rear end of the Prado.

[1coolbanana]

Marc, I assume the 825mm ride height is when set to "normal", therefore when ride height is set to "High", height will be at 865mm? Thats getting close to nose bleed territory!! (well, not quite.. but its good!)

Yeah, normal mode.
I wouldnt use Hi setting, doesnt leave any down travel.
I may disable the switch or at least just not use it.

[1coolbanana]

This only happens with extreme articulation, I have managed to flex the rear down as far as 945mm with the shocks extended and up as far as 635mm hard on the bumpstop:

945 at the wheel doesnt necessarily mean the shock extends any further as the pivot point is around the lower shock mount. The wheel is outboard and the airbag is inboard so the airbaig wont be extending any more with the opposite wheel at full compression, as the angle increases, the extended airbag may well be "less" extended.

The TEMS Grande rear shock is exactly the same 375mm extended length as a standard Prado shock, but has 31mm less travel due to the TEMS mechanism inside the shock. Suspension Data is here: http://www.pradopoint.com/showthread...nsion-Database for comparison of rear shocks.

Ok, i will remove and measure mine tonight


Until "Hi" is selected on the ride height control, then it would sit at about 860mm, so just be a little a careful there. I have thought about it and look at it like this; a GXL standard ride height is 750mm front and 780mm rear. Add a bit of weight and full fuel and the rear levels down to around 770mm. So a comfortable compromise on the Grande is to set the rear at about 20mm higher than the front. So a 40mm lift is 790mm front 810mm rear, a 50mm lift is 800mm front 820mm rear. Any more and I would suggest longer shocks and longer air springs are needed.

I will be disabling the switch, seems pointless anyway.
Those numbers your quoting are what Im aiming for.
The only exception being, at 800F and 820R the sidesteps have a nose up appearance.
Im aiming for 790F and 825R.

The bolts for the brackets are 8x30 HT.
Didnt touch the adjusters, just mounted the brackets up so I could take them out and it goes back to exactly where it was and the adjusters are a hassle to get to and fragile.
Besides its easy to adjust with washers until I have it exactly where I want then I will machine up some spacers.

[craigm]

At 825mm ride height, its pretty good at the back.

Spacing out the sensor brackets.

Marc, I assume the 825mm ride height is when set to "normal", therefore when ride height is set to "High", height will be at 865mm? Thats getting close to nose bleed territory!! (well, not quite.. but its good!)

[1coolbanana]

I was in contact today with Mitchell Bros, and I asked them if their 'retaining solution' was fitted to my vehicle - seems they do NOT do anything in terms of retaining work on the airbags. They claim the only time the airbags dislodge is if the wrong shock (i.e. too short) is fitted.

"seems they do NOT do anything in terms of retaining work"

Funny, they wanted to charge me $300 for the "secret IP that they would not disclose" for retaining!!!
I think this is a widespread rort amongst some of the fitters around Sydney

[Peterpilot]

CV angles should be OK at 800mm http://www.pradopoint.com/showthread...l=1#post240479

With no other modifications apart from springs and shocks the most you can lift the front is 810-815mm (from bottom of rim to guard) at this point you are on the very limit of the wheel alignment adjustment. It's also pushing the CV angle a little too far but it's certainly not terrible and a reasonable service life could still be expected.

[Way2go]

So a good aftermarket shock that remains withing 10-15mm of the OEM shouldnt pose any problem with the airbags and still provide plenty of lift.
Thats my theory anyway

Seems a sound theory.

I was in contact today with Mitchell Bros, and I asked them if their 'retaining solution' was fitted to my vehicle - seems they do NOT do anything in terms of retaining work on the airbags. They claim the only time the airbags dislodge is if the wrong shock (i.e. too short) is fitted.

They recommended fitting Firestone replacement (longer) airbags if you want a big lift, but otherwise longer travel shocks will do the job.

820mm (or a little lower) looks about what I will set mine to.

Did some measuring of the front tonight. Currently sitting on 740mm using the middle circlip on the Bilsteins (no idea what model spring has been used though - not a long or strong one to only have that height I'm guessing), full droop is 865mm, so I can go to 800mm at the front with 60mm droop still available. Will be happy with 795 or so after settling.

I assume the CV angles aren't too bad if the front is sitting at 800mm? (Forgot to have a look at them while the front was jacked up.....).