100% atf in w58 ?

[fixeruperer]

hey all !!!!,
my w58 doesnt want to change into 2nd under power, its pretty annoying, i dont even drive the car anymore due to this. ive tried like a 30%atf 70% gear oil and didnt help, so i had the box rebuilt thinking it was synchro issues, i was wrong.

im thinking about throwing 100% atf in there, what do you w58ians think ?.
have any of yous had shifting problems ?, when i had less power like around 280-300 it would change, but now with 340+ it dont wanna.

i wanna smash 2nd !!!!! haha.

[river]

Hi,

I'd say your gearbox is rooted and no amount of oil is going to fix it. Get another box or get the one you got reconditioned. Changing oil to fix these sort of issues is, at best, a temporary solution that only delays the inevitable rebuild.

seeyuzz
river

[fixeruperer]

its just been rebuilt. its only done a few hours.

[thechuckster]

then take it back - who ever built it has obviously got the synchro gears/bits wrong for that gear set.

edit: or the shifter arm & rods are not right.

[fixeruperer]

yes, that could be it. when i had it built, he said that the synchro's he ordered were wrong and he had to source other ones.
sad thing is, its been too long to take back. ive lost out on that one. He wants to drive it, but it only fails when fanging it. he will prolly crash it or stay on limiter haha.

tho, the problem im having now, is exactly the same as before, prior to rebuild.

if i cant get this sorted, ill have to save up for one of them gofast NZ gear sets, or stick a jatco 4 speed in.

cheers fellaz.

[YLD-16L]

1JZ-Rolla had the same issue when he had a W5x behind his 4AGTE (Phil might be able to provide more detail) as did a couple of other mates with same engine gearbox combos. Mines had 3 gearboxes and I haven't had the issue even shifting on the limiter has been fine.

We always thought it was an rpm related issue rather than power related. Never found the true cause of the issue though so it's just a hypothesis. The issue usually reared it's ugly head at the drags if I recall correctly and shifting at lower rpm avoided it. Not ideal or as much fun though

[NME308]

Toyman talks about similar issues with I think it was a J160 and he found a cure in a twin plate clutch as opposed to a heavy duty single.

I'm in the exact same boat with my T50 - take it to anything over 6500rpm in anger and 2nd is simply NOT in the gearbox...

My brother used to perform a mod to the agricultural aussie 4 speed holden box which he learned off real old timers i.e. file every 2nd dog tooth off the synchro rings. Amazingly enough you could flat shift the things at 7000rpm although the pitiful creatures still broke like chalk.

Be interesting to see if there is any consensus on one or more 'fixes'!

Cheers,
Jason

[1JZ-Rolla]

1JZ-Rolla had the same issue when he had a W5x behind his 4AGTE (Phil might be able to provide more detail) as did a couple of other mates with same engine gearbox combos. Mines had 3 gearboxes and I haven't had the issue even shifting on the limiter has been fine.

We always thought it was an rpm related issue rather than power related. Never found the true cause of the issue though so it's just a hypothesis. The issue usually reared it's ugly head at the drags if I recall correctly and shifting at lower rpm avoided it. Not ideal or as much fun though

Yep, YLD is pretty much on the money, mine would baulk at 2nd gear in particular, once I fitted cams & upped the RPM shift point on my 4AGTE/W55 combo. Previous to the cams i'd shift at around 6500 rpm cause it ran out of puff, it would select gears no problem. As soon as I upped the shift point to 8000rpm the box wanted nothing to do with 2nd gear....... wouldn't crunch or anything, would just refuse to let you push the lever past neutral, until the revs came back down.

Tried a blend of 50/50 VMX80/Dexron III ATF, which would then allow it to go into gear with a bit of a crunch, but certainly not ideal.

My gearbox was never rebuilt though, just a general wrecker issue ex Toyota Corona.

Never really got to the bottom of it. Let us know what you find though!

Cheers
Phil

[oldcorollas]

synchros don't know how much power the motor is making, as you shift with the clutch in.
the speed differential between the input and layshaft plus the clutch friction plate, and the mainshaft via the synchro is the problem.

lighter friction plate (or less drag between the pressure plate/flywheel and the friction plate) will allow the input side to slow down faster and slip into gear easier... it's the momentum/inertia of the input stuff you have to either overcome with synchro friction... or time... time is easier and cheaper

ATF is supposed to increase firction at the synchro surface... but the surface area of a synchro on a shiny cone, vs the momentum of the input stuff when the speed differential is too great = hard work for synchro.

try shifting progressively slower and see if it makes a difference?

if you want to "smash 2nd", put dogs on 2nd

edit: what i'm tryin to say is, sometimes the difference between a "good box" and a "bad box" is mechanical sympathy.... (or synchro design )

[1JZ-Rolla]

Well summarised oldrollas. Makes a lot of sense.

[Bazda]

Possibly running a twin plate clutch setup will help. They release much faster than the normal ones allowing for better gear changes.

[1gjet]

I noticed 2nd was a bit shabby in my w58 was always fine in low revs and load but 7-8+ on boost it would go in with a crunch, ended up running 50/50 dexIII which helped but didnt save its fate in the end. completely stripped 2nd. I solved that with a twin plate and j160 which has always been perfect. So i think twin plate is the go

[andrew_mx83]

i run all my boxes on 100% SYNTHETIC atf as soon as they get noisy or hard to shift.... works a treat, and usually buys a few months until it goes bang. goes into gear much easier too.


maybe try double clutching? also solves any syncro issues and can be done lightning fast with a bit of practice.



ive now got a j160 for my 9000rpm build, wondering if i will have issues...

[1gjet]

Andrew, my j160 has seen up to 8800 and was fine. You just have to be nice to them on the shifts otherwise KABOOM

[oldcorollas]

double clutching is for going DOWN through the gears... (using engine to speed up the input shaft)
or when your shift time is so long, that the input shaft slows down too much before you get it into gear...

ie, you rev it while in neutral to increase the input shaft speed...