Jx 4 speed or 5 speed

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Van Rouge
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Jx 4 speed or 5 speed

Post by Van Rouge »

I have aways found the 4 speed transmission on my JX a bit short am I better to get diesel 5 speed box or not? The dog leg is not an issue just would prefer more evenly spaced gears and a bit of "overdrive" options please Cheers guy

multisi
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Re: Jx 4 speed or 5 speed

Post by multisi »

The JX diesel engine should be mated up to a 5 speed box, but there are lots of ratio variants so you need to choose the right one, the code markings for a 5 speed box that went with the JX were ASS, this gearbox had good ratios for higher speed driving, there isnt an overdrive with the 5 speed .
1992 red lle 2.2 subaru 1990 rhd caravelle 2.2 subaru 1986 california import vanagon

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ZsZ
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Re: Jx 4 speed or 5 speed

Post by ZsZ »

There are not much differences in the gearbox overall ratios on these vans.
Like 3H is 95 kph AAP is 100kph @3000 RPM and the AAP is one of the longest 4.57 diff boxes.
You can get another 10kph and have 110@3000 going custom 4.14 R&P and a bit more with custom 5th and 4th.
But that needs tdi power and torque.
Zoltan
1986 Multivan ex-Caravelle. Van since 2006, running mTDi 1Z since 2008 with Fiat Croma 1.9 TDid pump 2008-2019, custom pump since 2019
5spd custom box 4.57 diff + 0.74 5th

multisi
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Re: Jx 4 speed or 5 speed

Post by multisi »

There are big differences with the gearboxes fitted as standard to the T3 , some gearboxes fitted to the lower powered diesel models would not be good at motorway speeds fitted to a Jx engine van. 
1992 red lle 2.2 subaru 1990 rhd caravelle 2.2 subaru 1986 california import vanagon

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Aidan
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Re: Jx 4 speed or 5 speed

Post by Aidan »

what code box is fitted ? 4 speed JX was unusual, ABH is the code that should be in there, 5.43 final drive with a 0.78 4th gear, just like a TD Syncro 14", low enough 1st, quick through the gears, slight gap 3rd to 4th; 6 and a half percent slower in 4th than the 3H/ASS 5 speed turbodiesel box is in 5th gear

Van Rouge
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Re: Jx 4 speed or 5 speed

Post by Van Rouge »

Thanks for the replies all, Hi Aidan will need to check my Van is in for restoration at the mo
Cheers
Nick

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