Club 80-90 Forums

How can you tell if a 2wd gearbox has a taller 5th fitted when it is out of a van?

Can you tell by counting the teeth on 5th gear?

Any advice appreciated.

the taller 5 speed gearbox has the code AAP

mark

the 4th or 5th gear is not much difference ,its the final drive(diff) that determines things, see here
http://www.brick-yard.co.uk/VehicleSpec ... fo/gbx.htm
mm

mark richards wrote:the taller 5 speed gearbox has the code AAP

mark

Ah did not make myself very clear, i have several AAP boxes and one which is meant to have had a taller 5TH gear fitted for TDI use etc. I cannot remember which one has the taller 5th fitted so wondered if there was a way to tell while they are out of the van etc?

Hope that makes sense and thanks for your help.

metalmick8y wrote:the 4th or 5th gear is not much difference ,its the final drive(diff) that determines things, see here
http://www.brick-yard.co.uk/VehicleSpec ... fo/gbx.htm
mm

Cheers for that mate, i didnt explain very well. The longer 5th i am taking about is a custom one for TDI use etc.

well if you restrain one cv drive and then rotate the input shaft when its in 5th and count the rotations to acheive 1 on the free cv flange you will get the figuer with some simple maths , might need say 5 rotations to confirm an average ,this said it will only give yoiu the final ratios and i suppose you would need to know the diff ratio to deduct from this .hmm
maybe aiden has an easier way
mm

The one that shows signs of being dismantled maybe? Unless they have all been cleaned.

Typical final drive ratio's are slightly higher than 1 : 1 so I suppose a crude but effective way of telling would be to mark both input shaft and output flanges, put it into 5th, then turn the input shaft say 20 full turns whilst counting the number of turns the output flange turns (lock one flange)

The more turns on the input shaft the higher the accuracy of the result.

The higher geared box will turn it's output flange maybe 1 turn more (thats a guess but it won't be much).

Martin