4wd problem on 3rd gen - mechanic says new diff/axle needed?

[thibaud]

Hi,

I've had an issue with the 4wd not engaging since I the truck to extract timber with the 4wd engaged. That day, when I got onto the road, fully loaded, the 4wd took ages to disengage and ever since then, the propshaft turns but the diff doesn't engage, with dash light flashing.

I put the truck in last week so that they could have a look at it and without looking inside the differential, his verdict is that the diff is broken, sheared tooth perhaps and that I should replace the whole axle. Obviously axle are hard to come by (1996 3rd gen) and I was wondering if he had exhausted all possibilities. I heard about ADD, vacuum pump and other technical issues that I struggle to understand so I am not sure what to do.

Do any of you technical boffins have any advice for a mechanically ignorant soul?

[Surf01]

Doubt it very much as mine only required a minor adjustment. I am sure that someone will be along to advise the mechanic may be incorrect in his diagnosis.

[lord lucan]

if he can turn the rear prop its either diff or halfshaft [i have both] as long as your diff code is a02

[thibaud]

In fairness, not too sure what he thinks I need. He said getting a whole axle would be the easiest rather than repairing the diff. Frankly, I am just not convinced about the diagnosis but my lack of technical knowledge means I don't know how else to approach it.

[TonyN]

Any flashing light 4wd issues will have nothing to do with the diff or axle. Its a transfer case thing, and probably only a switch jammed, don't let anyone take the 4wd solonoid apart till all the position switches are checked.

When you say the 'prop' is spinning but diff not do you mean it won't move, or do you mean the front prop is moving but 4wd not working?

[thibaud]

Hi,

The front prop engages and turns but the 4wd doesn't engage. There's all sort of flashing going on as you go through 4wd, hi4 and lo4 but it never clicks as it did when it engaged before.

The last time I took it out of 4wd, the car was loaded with 6ft length of Ash and the suspension very compressed. Would that potentially damage anything?

Never had any issues before and it has never re-engaged since.

[ian2144]

I take it you have tried the old forward and reverse trick with sharp stab on the brakes. ????

It's worked for me in the past, if you do not use your 4WD regularly some time the solenoid sticks on .


Ian........

[TonyN]

I've known the yanks to manage to break the centre diff, just usually only with huge tyres and rock crawling, not seen a broken one in the uk. Usually it's a duff switch thats just gone.

Hard to tell without seeing it.

Hi,

The front prop engages and turns but the 4wd doesn't engage. There's all sort of flashing going on as you go through 4wd, hi4 and lo4 but it never clicks as it did when it engaged before.

The last time I took it out of 4wd, the car was loaded with 6ft length of Ash and the suspension very compressed. Would that potentially damage anything?

Never had any issues before and it has never re-engaged since.

[J i m s t e r]

It seems to be a feature of 3rd gens that the 4wd doesn't engage instantly if it's not used frequently.

One that works for me when I want the orange light to make it's mind up is to knock it into neutral, back into D, then give it some revs. If this fails, disengage the 4wd button, and re-engage. Repeat.

Has always worked within a few mins of trying.

[thibaud]

Thanks for the advice, sorry I haven't been on the forum to reply until now. Anyway, as it happens there has been some development. I cleared a fallen tree off a riverside on Wednesday and managed to get the truck stuck in soft mud/grass. Anyway, on the off-chance I engaged 4wd and despite not hearing the familiar clunk and the light going doolaly, the truck unstuck itself straight away. I tried a few times, the back wheel spinning in the grass in 2wd but not in 4wd. The H4L doesn't engage though. I can put it in H4H but it won't go back up into N or H4L.


Does that point the fault to a switch or something similar. I'm pretty sure I used to hear a clunk when engaging 4wd but perhaps I remember that from my Trooper!


Is it worth putting it in a Toyota dealer? I need someone that knows the mechanics of it to have a look as just 'swap the axle mate' simply doesn't cut it! I wish I'd know more about mechanics but in any case I haven't got anywhere to stand the truck to do so anyway.

[TonyN]

Can you get it up to me sometime?

[thibaud]

You're in Basingstoke right? That might be the best thing to do. The earliest I could do would be Thursday 23rd Feb or Friday 24th. Let me know if that might work. I wasn't sure you still were in business.

[TonyN]

Thats no problem, remind me a week or so nearer the time.

[thibaud]

Sorry about the delay in responding, problems with broadband. Anyway, that should be fine so I will call you the week before to confirm or arrange another time. Thanks.