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Jacks transmissions


buster

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I have had a couple rebuilt here in Finland. There's nothing special about it. The pullers might need to be modified if thy arent made for a Getrag. The gears are really tight, so you need quality pullers.

 

Mine had synchros changed and one had the gear selector fork break.

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they are a transmission specialist , bloke there just said we shouldnt have any problems doing it , I think he thought I wanted them to remove the gearbox then strip it down coz he quoted me £600 plus any parts that need to be replaced

 

I would love to learn how to referb the box myself but it seems a massive job

 

 

thats Joe Hussain doing the referb there and he said he would do mine but i think its going to cost an absolute fortune to send it to and from the states

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Hi Krister, did you use the transmission for drag type gear changes? Or even drag racing? How much torque were you putting through it, do you know? Thanks. I am well aware of how tight some gears are on the shafts and the fact sometimes cutting them off and renewing them, even if they were OK, is the only way.

 

Have done some drag racing, but I hurt the synchros with a bad clutch which didnt disengage fully. Not sure why the gear fork broke, wasnt pushing the transmission at that time very hard.

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There's nothing trick about them, it's just people have to accept the price of the bits, and sometimes if a

gear or synchro hub will NOT pull of it needs to be destroyed to get it off. They are also time consuming to do.

Probably a good eight hours plus solid with it on the bench. Without "issues".

 

Plus, don't forget no sane person will warrant a road car gearbox used for none normal road usage. So you can probably forget

warranty claims if you have 700 BHP or are fond of drifting, track days or (shudder, the worst thing a transmission can suffer...) drag racing.

 

For example, here's a little bit of this company's exclusion clauses:

 

"Purchaser understands, recognizes, and acknowledges that all parts and services manufactured or sold by Jacks Transmissions are warranted

only under normal driving conditions. All warranties will be absolutely and permanently null and void if any vehicle our products and/or services

are installed in, is used for, racing purposes or abused."

 

 

So expecting a rebuild to be warranted if you have it behind some single turbo beast is probably highly optimistic.

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Have done some drag racing, but I hurt the synchros with a bad clutch which didnt disengage fully. Not sure why the gear fork broke, wasnt pushing the transmission at that time very hard.

 

 

Clutch drag, and clutch preload can do SO much damage to cranks, (thrust failure) and synchros. If you have to mash the clutch pedal into

the carpet to get it into gear, or there's no free play in the pedal and clutch arm with push type clutches, expect BIG bills.

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I need to assess the price of parts, their availability long term, as best as I can tell, and to some extent potential demand.

I don't want to commit to anything just yet, I am way behind with stuff as it is, due to various "issues" here. Let me ponder a while :)

 

 

Race transaxles are joy to work on as they are designed from the get go for easy disassembly and rapid gear replacements. Road car gearboxes are usually the exact opposite :)

 

But thanks for your interest!

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