How to modify the A.D.D. for trouble free operation.

[BUSHWHACKER]

but the only thing im worried about vince is now the front diff is 'active' how will the TC act to different rotations of the front and back prop shaft. i only fit the front PS when i go off roading its not on any other time. i know i should get free wheeling hubs but for need to save up for £120 a pair or shouldnt it matter???

It's basically the same as before, except the pasenger side driveshaft is now connected to the diff.
You can still drive around in 2WD as before then press the button to engage the front propshaft/diff. when on the loose stuff.
Totally up to you if you want to fit the hubs, but they're not really necessary unless you've cranked your torsion bars right up.

[Sancho]

Good write up Vince. Same (ish) question as Dieselboy; does this mod mean that the front prop is now permanently engaged with the front diff and turning as you move. If not, what connects the front prop to the diff or was it always locked in anyway?

[BUSHWHACKER]

Good write up Vince. Same (ish) question as Dieselboy; does this mod mean that the front prop is now permanently engaged with the front diff and turning as you move. If not, what connects the front prop to the diff or was it always locked in anyway?

When in 2wd, the front prop spins because the front wheels are turning.
When in 4wd, it's the transfercase that engages/disengages the front prop/wheels.


In standard set up and 2wd, the passenger side front wheel isn't connected to anything, so it just free-wheels, but the driver's side is permanently connected to the diff/propshaft.
Select 4wd and the passenger side wheel engages at the same time as the transfercase.

This mod just keeps both front wheels permanently engaged to the diff,so you're not relying on the vacuum, which can play up at inconvenient times.

Hope I explained that OK.

[POPEYE]

You certainly have explained it, an excellent write up mate, i may have a go at this as i hate all things of a vacume nature, the headlights (swivel) on the Buick were vac opperated and s0ddin useless as there the vac wipers on an old Ford consul, it only takes one pipe to come off or split and you've a bugger of a time finding it,
i already have free wheeling hubs due to the sus lift, i wish there were a cheap way of altering this (in my view) stupid non limited slip front diff arrangement on these trucks, i wound mine up once not knowing it was in 4wd(had the dash in bits and no warning light), seems daft to me to not to be able to have 4wd engaged all the time, not that ya'd need it but it would do away with the worry of locking up the diff, mine takes a few seconds to engage so i guess this mod would make it "instant".

[nos4ra2]

Thanks for that Bushwhacker-I was thinking of doing something like this myself and you've just saved me a lot of time

[wishbone]

Can you still switch into 4WD while driving with this mod ?

If yes does it mean the people with 2.4's can ditch the alternator with the vacuum pump on it ?

[TonyN]

If yes does it mean the people with 2.4's can ditch the alternator with the vacuum pump on it ?

Only if you like using two feet on the brake pedal to stop.

[wishbone]

Only if you like using two feet on the brake pedal to stop.

Hehe!

Learn something every day - I assumed the brake servo ran off the manifold pressure same as petrols...

[nos4ra2]

Can you still switch into 4WD while driving with this mod ?

Yes,but don't try to switch into 4WD while driving with the manual hubs disengaged-I don't think it'd be too good to try to engage a stationary prop while the gearbox is turning!

[Damien95]

It makes it the same as a Hilux pickup. The don't have ADD.

Mine does have ADD.

[Red hilux]

Yes,but don't try to switch into 4WD while driving with the manual hubs disengaged-I don't think it'd be too good to try to engage a stationary prop while the gearbox is turning!

Ive fitted a second switchin series just for this.

Ive bumped 4wd on once before while driving




This mod is an awesome mod. Great write up mate

[bronx89]

Very interesting mod and I'm quite keen on doing it to hopefully resolve my 4WD issues on my '95 KZN130 3L TD Auto.

BUSHWHACKER could you please refer to the first post in this thread to review my issue and let me know if this will sort both the sticky 4WD issue and the front drive shaft constantly engaged issue?

http://www.hiluxsurf.co.uk/showthrea...829#post806829

Cheers.

[Siena]

Good write-up on this. ADD is standard on the MK5 Hilux truck.. I'll be carrying out a similar modification on mine when I commence the engine swap.

[Jameswallace]

Im yet to have trouble engaging 4wd but once i do i will also do this

I engage 4wd once a week to keep everything working