Which gearbox.

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HappyCamper
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Which gearbox.

Post by HappyCamper »

Hi, Anyone know what the best gearbox would be best to run with a golf agg engine. I'm presuming the original 1.6 diesel box will be too low gearing, is a petrol box a better choice. 

cobblers
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Re: Which gearbox.

Post by cobblers »

AAG has the power to push a taller gearbox along, so an AAP or something similar (from a 2.1) is fine. Unless your van is especially heavy, the taller the better.

davidoft1
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Re: Which gearbox.

Post by davidoft1 »

I have an AAP near Portsmouth

HappyCamper
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Re: Which gearbox.

Post by HappyCamper »

I'm not well versed with bthe options, so please bear with me. Using the AAP box would require my diesel bellhousing.to mate to the engine. Does the bellhousing bolt straight to the AAP  gearbox. do I use the diesel primary shaft. Are the gear linkages the same or does it need specialist linkages. Thanks.

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Aidan
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Re: Which gearbox.

Post by Aidan »

AAP is a 5 speed; you can use it with the 4 speed linkage but it will be like driving a Syncro, you'll have to go under the gate to get 1st gear and do the side to side thing when going from 1st to 2nd, its not an issue on a Syncro cos we only really use G when off road and don't often change up to 1st on the fly, but we get used to doing it.
Ideally you'd change the front half of the linkage and the gearstick to the 5 speed versions
The bellhousing is interchangeable but you'd also need to swap the input shaft over or cut 11mm off the installed petrol one (which is a hack, but understandable, swapping input shafts on 4 pinion diff boxes - all 2.1 petrol boxes - is a bit more fiddly than on a 2 pinion diff) but it is doable
AIDAN :)

cobblers
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Re: Which gearbox.

Post by cobblers »

Aidan wrote: 14 Mar 2026, 10:35 AAP is a 5 speed; you can use it with the 4 speed linkage but it will be like driving a Syncro, you'll have to go under the gate to get 1st gear and do the side to side thing when going from 1st to 2nd, its not an issue on a Syncro cos we only really use G when off road and don't often change up to 1st on the fly, but we get used to doing it.

I had always wondered what happened whether you could get away with this!

I had a fairly long 4 speed box on my old Gti van and it was probably better to drive than the 5 speed AAP I replaced it with. The AGG has a pretty wide spread of power so a 4 speed box works well with it, and you don't have the complexity of dogleg first to deal with.

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