Automatic Disconnecting Differential (ADD)

[swagman]

Hi All.
I have a problem with (I Think) the ADD system in my Surf. What Happens is this…After a recent trip (about 4 Days later) a horrible grinding noise started, it sounds Like 2 spline gears not engaging right. just rolling around at the ends (not slipping together) Action: take the end Flange off the hub (to stop the left hand drive shaft from turning) no more noise but no more 4wd It even makes the noise when 4wd button is pressed in driving around.
Had the Surf on a Hoist today with all 4 feet dangling (looked very sad) put the flange back on the hub started it up & put into 4wd to see if it worked & it did. Was it Because it was hanging on a hoist with no load? & when on the ground it has more load eg weight of the surf?
Any ideas would be appreciated. 1 confused surf owner & another confused mechanic
John

[silvtr1000]

I can't really help, other than to say that if it is a problem with just the hubs, it might be the perfect opportunity to just replace them with manual freewheelers (Around £120 to £200 or so with all the bits from Milner Off Road or 4x4 Tyres & Accessories). Many owners do change them anyway - it stops the front driveshaft turning while in 2WD, reducing wear on all the related bits. When I can sneak the credit card (my own! but it really is for my own good, aparrently...) from wherever the latest place she's hidden it, I'll be getting some.

It may be a problem with the splines on the end(s) of the front half-shafts (axles? - the ones that actually drive the wheels, whatever they're called).

Someone with more technical knowledge than me will be along soon, have no fear...

Welcome aboard!


Mark

[da SLUG man]

sounds exactly like mine, but oil pours out the diff aswell on mine... i think it's the inner CV collapsed, letting the splines slip out and making the noise when they just make contact..

do your shafts move in and out?

[swagman]

Hi

1) Free wheeling hubs would not fix the problem, cause as soon as you lock the hubs in the problem would still be there.

2) there is a wee bit of movement in & out maybe 5mm, we are going to try & fit a washer behind the Flange plate (Hub) to force the drive shaft back & take the slack out & see what that does Also there is a bit of play in the wheel bearing which will get adjusted at the same time.

Thanks so far for your idea's keep them coming

John

[NiftyNev]

Hi

2) there is a wee bit of movement in & out maybe 5mm, we are going to try & fit a washer behind the Flange plate (Hub) to force the drive shaft back & take the slack out & see what that does Also there is a bit of play in the wheel bearing which will get adjusted at the same time.

John

This is a little hard to explain why but do not do this.I can see more damage being done.I have dismantled the front end on mine a couple of times and have a pretty good idea on how it all works and I would not recommend it.

Neville

[swagman]

Nev
Since you have dismantled the front end before, can you tell me if you have
a bit of spline sticking out from the outside of the flange
or does the d/shaft finsh flush with the outside of the flange plate

John

[Guest]

Hi All.
I have a problem with (I Think) the ADD system in my Surf. What Happens is this…After a recent trip (about 4 Days later) a horrible grinding noise started, it sounds Like 2 spline gears not engaging right. just rolling around at the ends (not slipping together) Action: take the end Flange off the hub (to stop the left hand drive shaft from turning) no more noise but no more 4wd It even makes the noise when 4wd button is pressed in driving around.
Had the Surf on a Hoist today with all 4 feet dangling (looked very sad) put the flange back on the hub started it up & put into 4wd to see if it worked & it did. Was it Because it was hanging on a hoist with no load? & when on the ground it has more load eg weight of the surf?
Any ideas would be appreciated. 1 confused surf owner & another confused mechanic
John

How about the inner hub bushes that the drive shaft runs in.

Cheers

[rich]

Heres some ADD info if it helps.

Rich.

http://www.afm15.dial.pipex.com/surf...l%20system.pdf


http://www.toyotasurf.asn.au/techsite/add.htm

[NiftyNev]

Nev
Since you have dismantled the front end before, can you tell me if you have
a bit of spline sticking out from the outside of the flange
or does the d/shaft finsh flush with the outside of the flange plate

John

John

Can't remember if there was any of the spline showing.

Lets see if I can explain this.The drive shaft has some end float.This should be no more than 1mm.There is a circlip/snapring and spacer on the drive shaft and end float is measured between the two while pulling the shaft outwards.The specs for this are 0.075mm - 0.690mm normal with a maximum of 1mm.

If more than 1mm you need to measure the thickness of the spacer.These are available in sizes 1.8mm & 2.25mm.If end float is more than 1mm and the existing spacer is the 2.25mm one then the steering knuckle bushes are worn.If the thinner spacer is installed then replace with the thicker one and end float should be ok.

Hope that makes sense.

Neville