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When you say I need a diff, do you mean I have to replace the whole thing or I can keep what I have and just swap the crown wheel with one from the years and model you mentioned?
When you say I need a diff, do you mean I have to replace the whole thing or I can keep what I have and just swap the crown wheel with one from the years and model you mentioned?
The crown wheel & pinion should be kept together as a set, I'm tempted to phrase that as MUST be kept together as a set, but, in a life or death scenario you can certainly swap one with out the other, just be aware that you will destroy both and in a very short space of time. The last step in manufacturing the gear set is to lap the crown wheel & pinion as a matched pair, after which they should never be separated.
It's also important that you recognize that you can NOT swap the pinions between the different ratios, they might be both eight tooth pinions, but the angle & size of the teeth are going to vary, what I've said above is specific to swapping the crown wheel or pinion between identical gear sets.
I see, thanks alot for explaining, I’ll have to find a whole diff with 10 bolts and a ratio that matches my rear diff then transfer the e-locker into it.
Ok so I managed to count crown wheel & pinion teeth in the rear diff and also the crown wheel teeth in the front diff through the holes (I couldn’t see the front diff pinion tho, only the crown wheel) and here’s what I found
Front diff
Crown wheel - 45 teeth
Pinion - I’m guessing 11
Ratio : 4.090
Using what I learned from the amazing people on this thread:
4.3/4.090 = 1.05
So this means for every full rear wheel rotation I get 1.05 front wheel rotation.
And this is the reason that when I put it back into 2WD after driving in 4WD it doesn’t disengage and I have to reverse, correct?
Ok so I managed to count crown wheel & pinion teeth in the rear diff and also the crown wheel teeth in the front diff through the holes (I couldn’t see the front diff pinion tho, only the crown wheel) and here’s what I found
Front diff
Crown wheel - 45 teeth
Pinion - I’m guessing 11
Ratio : 4.090
Using what I learned from the amazing people on this thread:
4.3/4.090 = 1.05
So this means for every full rear wheel rotation I get 1.05 front wheel rotation.
And this is the reason that when I put it back into 2WD after driving in 4WD it doesn’t disengage and I have to reverse, correct?
Correct, so 5 rotations of the rear puts the front out (it moves further) by 5 x .05 = .25 turns.
You don't have to reverse. you could just jack up one wheel, and there will be a "twang" and the wheel will flick round to relieve the tension.
Or you could bounce it over a kerb like an Alvis Stalwart/Saladin/Saracen/Salamander- when the wheel leaves the ground it unwinds..
Or just do nothing and soon there will be a "bang" as something breaks and you won't have the wind up any more.
It needs matching diffs before you use 4wd or you are going to break something. I wonder if the front one was broken, because it didn't match the rear and the mechanic matched the broken one that he took out.
If it suddenly breaks, go back to the last thing that you did before it broke and start looking there
I see, thanks.
Yes I already took out the prop shaft until I sort this out.
I doubt the old one was broken because of this as I never had issues with it for years and it always disengaged 4WD with no issues, never had to reverse.
Just to confuse matters slightly, if you are using 4wd as intended e.g. in situations where the tyres can easily slip, the difference in axle speed from having the wrong diffs actually makes very little difference and won't cause any harm. There is a far bigger discrepancy between axle speeds when you turn a corner, even if you have exactly the same diff ratios. The transmission is designed to be able to cope with this as long as you are driving in appropriate conditions.
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