Auto gearbox codes

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KarlT
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Auto gearbox codes

Post by KarlT »

Hi, Are there different box codes for the 1.9 & 2.1 engine? Where on the box will they be & what should I look for?
Cheers

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Aidan
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Re: Auto gearbox codes

Post by Aidan »

yes there are three different ones code is I believe stamped on cas below nearside output flange
NJ is the quicker box iirc

KarlT
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Re: Auto gearbox codes

Post by KarlT »

Ahhh Aidan, just the chap.
Had a look in haynes...........

Autobox...
Final drive......4.09 -1 or 3.74 -1
first gear........2.71 -1
second 'gear.....1.50 -1
third gear........1.00 -1

reverse...........2.43 -1

Now, what does that mean, I realise it different ratio's but what does it mean in layman terms & the autobox has only got 3 gears what is final drive?

:?

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Aidan
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Re: Auto gearbox codes

Post by Aidan »

final drive is the rear axle ratio, in the case of your auto either 45/11 or 41/11, in real terms there are 11 teeth on the head of the drive shaft from the gearbox and 41 or 45 teeth on the crown wheel on the rear differential which turns the drive shafts so that the rear wheels turns once for every 3.7 or 4.1 rotations of the drive from the gearbox

the lower the final drive ratio the quicker the van will be for a given engine speed

thus everyone 2wd looking for a box generally wants 4.57 fd manual gearboxe to make their bus go quick or be more economical or keep the revs down in the acceptable range (TDi) and the 5.5 and 5.83 ratio boxes from the 1.7KY diesel are not much use except for the gears and mainshaft and cases, hence the perpetual search for the mythical DK box which was the 4.57 box from the 2 litre Aircooled van.

In the autoworld everyone wants the 41/11 box, especially the yanks who never got it.

KarlT
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Re: Auto gearbox codes

Post by KarlT »

Cheers for the full reply. Its all alot clearer now!

So back on the auto box.......in third.......the engine turns once to the gear..1 for 1, And the gog/gear turns 3.74 times to turn the final drive, which in turn turns the wheel 1 for 1. Is that right?

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Aidan
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Re: Auto gearbox codes

Post by Aidan »

yes

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