4722 replies to this topic

[vocky]

three on ebay   

 

https://www.ebay.co....T4AAOSw7GRZLZz3

 

https://www.ebay.co....M4AAOSww1Fa3H4m

 

https://www.ebay.co....jgAAOSwSZBbdhsU

[Nev]

Thanks Vocky, maybe if I get desperate I might take a punt on a random stranger's gearbox, but ideally I would like one from someone known/reputable to minimise the chance of buying a shitter.

 

I'm going to have to swap my Quiafe diff into the new box, so if the box is a dud I will be wasting time and money - and I don't like either of those!

Edited by Nev, 02 September 2018 - 03:19 PM.

[ditonics]

Nev a 12 - 17 year old gear box is always going to be a punt unless you are very luck and get to drive the donor car first.

Good luck

[Nev]

Nev a 12 - 17 year old gear box is always going to be a punt unless you are very luck and get to drive the donor car first.

Good luck

 

Yea, it's such a lottery. I am considering getting an exchange / refurbed one (with totally new bearings throughout), though they'd have to agree to stick my Quiafe into the new one and drop the FD down to 3.95:1.

 

Even that will be a punt, as I've heard of a few refurbed ones that failed within a few miles.
 

Edited by Nev, 02 September 2018 - 03:39 PM.

[ditonics]

Talk to Steve Milton.
He seems to think there are OEM ones available in Germany. Not refurbished

[vocky]

get your gearbox repaired, then you know it's good

[MAXR]

Competition transmission services. They're good, they've rebuilt 4 gearboxes for me in the past 3 years & also a VX box

[Nev]

Done a bit of ringing round and thinking and the upshot is I am considering buying an old DZ F23 gearbox, a new set of bearings and make a Frankenstein new box of my own, taking the least worn gear clusters from which-ever, and swap the crown wheel and pinion for the 3.95 ratio.

 

Still waiting on a couple of quotes from professional places, so lets see what numbers and warrantee info they come up with...

 

As is often the case on my VX220 though, doing it myself is always the fastest, certainly the cheapest and quite often the most reliable way to ensure it's done right (not that I've ever rebuilt a gearbox!).

Edited by Nev, 05 September 2018 - 05:31 PM.

[siztenboots]

I have a spare one here you can rob for bits.

 

On my installed GB, I have noticed a lot of side to side play in the selector shaft , plus the nylon square bush is causing massive play , about 130,000 miles.

 

Shame as I was up at Minchinhampton Common this weekend, I could have chucked it in a hedge for you.

[Nev]

Competition transmission services. They're good, they've rebuilt 4 gearboxes for me in the past 3 years & also a VX box

 

Thanks, i've asked them for a quote.

[Nev]

I have a spare one here you can rob for bits.

 

On my installed GB, I have noticed a lot of side to side play in the selector shaft , plus the nylon square bush is causing massive play , about 130,000 miles

 

Thanks, is it an "AF" 3.65 final drive one?
 

Edited by Nev, 05 September 2018 - 05:37 PM.

[siztenboots]

just bog standard 3.65 , only difference on this one is the breather and fill up bungs.

[Nev]

I have a spare one here you can rob for bits.

 

On my installed GB, I have noticed a lot of side to side play in the selector shaft , plus the nylon square bush is causing massive play , about 130,000 miles.

 

Shame as I was up at Minchinhampton Common this weekend, I could have chucked it in a hedge for you.

 

Did you rebuild your current box then, which is why you still have some bits left over? How melted were your selector forks?

 

Watch out for cows on Minchinhampton - they are kamikaze!
 

Edited by Nev, 05 September 2018 - 05:44 PM.

[Nev]

just bog standard 3.65 , only difference on this one is the breather and fill up bungs.

 

I'm keen on lowering the final drive though, so as kind an offer as it is, the final drive on your left over box won't be right.

 

The "issue" I'd like to work around is that the engine revs so high, that 5th gear isn't required till 160 leptons, so I usually find myself driving around in just 3rd and 4th gear. With a substantially lowered FD I could then use 3rd + 4th + 5th gear and be able to stay in the power band better (with narrower step between gears obviously).

 

Also, with TC on my car (assuming it works) then having lower gearing (ie higher wheel torque) I will be able to accelerate harder/safer.

 

Edited by Nev, 05 September 2018 - 05:43 PM.

[siztenboots]

box #3 on the car came from Steve Turbo Spares ebay , colchester area, as box#1 had problems with 2nd jumping out. 

 

the spare one , box #2 has never been fitted as I tried to split it , I think I made the mistake on not locking one of the shafts.

[siztenboots]

I thought you had a LSD ?

 

Can you use the same output shaft ?

[siztenboots]

been a long time since I looked at the F23 , but this might help

 

F23 internals

Left to Right: 1st Drive Gear, 2nd Drive Gear, 5th Drive Gear, 3rd Drive Gear, 3-4 synchronizer Assm., 4th Drive Gear.

 

 

 

-Facts to remember are 1st, 2nd, and 5th drive gear are cast as part of the input shaft meaning they always turn with the shaft, 3rd and 4th drive gears only drive at the speed of the input shaft when the synchronizer sleeve (which is splined to the input shaft) is locked into either gear.

 

Next we have the Countershaft.

 

Top to bottom: Countershaft Final Drive, 2nd gear #1 driven, 2-1 synchronizer Assm., 1st gear #1 Driven

 

 

-Facts to remember are, the Countershaft final drive gear is part of the shaft, 1st and 2nd #1 driven gears are only splined to the shaft via the synchronizer being engaged to the gears.

 

And lastly we have the output shaft.

 

Left to Right: Final Drive, Rev final driven, R-5 synchronizer Assm., 5th Final Driven, 3rd Final Driven, 4th Final Driven

 

 

 

-Facts to remember are, the Big gear just to the right of the Final drive gear spins freely on the shaft along with the 5th gear final driven until either is selected with the synchronizer sleeve. 3rd final driven and 4th final driven are part of the output shaft and obviously are always engaged with it.

 

1st Gear: Begins with the first gear from the left on the input shaft. Power is transmitted to the 1st gear #1 driven gear on the countershaft (Big one on the bottom) when the shift fork engages the 1-2 synchronizer into the 1st gear position. The gear is locked to the countershaft and power is transmitted through the shaft to the countershaft final drive which meshes with the second to last gear from the left on the output shaft. From there it turns the final drive gear which of course, turns the differential.

 

2nd Gear: The shift fork on the countershaft moves back out of first gear position and into second. The second gear from the left on the input shaft drives the 2nd gear from the bottom on the countershaft which is now locked to the countershaft via the synchronizer. Again it drives the Countershaft Final drive gear which meshes with the second to last gear on the output shaft transmiting power through the output shaft to the final drive gear, into the diff.

 

3rd Gear: Much simpler then 1st, 2nd, or reverse. 3rd is engaged by sliding the 3-4 synchronizer sleeve toward the left locking 3rd drive gear to the input shaft, this transmits power to the second to the last gear on the output shaft which again, is part of the output shaft, turning the differential.

 

4th Gear: Similar to 3rd the synchronizer sleeve is slid to the right engaging 4th drive gear and locking it to the input shaft. That gear drives the gear furthest to the right on the output shaft which is also part of the output shaft, Driving the output shaft and the differential.

 

5th Gear: 5th Gear is simple like 3rd and 4th however instead of locking the DRIVE gears to the input shaft they are ALWAYS part of the input shaft which means we have to Lock the DRIVEN gears to the output shaft. In this case the biggest gear (3rd in from left) on the input shaft is the drive gear, again note it is part of the shaft. Its mating member on the output shaft rotates freely until we slide the 5-R synchro towards the right. This locks the 5th Driven gear to the output shaft which turns the Final drive gear.

 

Reverse: Reverse is unique in this transmission since it uses 1st gear componants. The power flow moves from the first gear on the left of the input shaft, through the largest gear on the countershaft (which spins freely on the countershaft since the synchronizer is not engaged and it rides on the shaft with a roller bearing) This big gear then drives the Large gear 2nd in from left on the output shaft, but since there is an extra step in the gear train the output rotation is reversed. A good way to look at this is that an odd number of meshing gearsets will allow both input and output shafts to rotate the same direction, an even number of gearsets will allow the input and output shafts to rotate in opposite directions.

 

[Nev]

I thought you had a LSD ?

 

Can you use the same output shaft ?

 

If I drop the FD then I need to swap out the pinion and crown wheel from the 3.95 box, and put the new crown wheel onto my Quiafe ATB. Should be simple.
 

[fezzasus]

Sorry to hear this Nev. I had an optimistic look to see if GM had brought out any new gearboxes in the last few years to no avail. 

 

Perhaps time to revisit just how much work is needed to make a F40 fit? 400 N.m factory rating rather than 230 N.m means it should be much more sturdy.

[siztenboots]

what is actually more sturdy , more metal on the gear sets , or the bearings?