Woodsport longer 5th gear

[Cattwooduk]

Watching this one with interest, my 5th gear only has about 5-10mm of 'nod' at the moment so wont need dealing with immediately, but I think my synchro is worn as sometimes changing into 1st or 3rd takes a bit of a push... then again it might just be linkages, I'm yet to check there.
When I get round to changing the synchro, if this mod works out without too many parts needing replacement I might go for it myself, longer 5th gear would indeed make cruising a bit better, not to mention slightly less noisy.

[Clarky_X]

Paul, I'm not really familiar with the internals of gearboxes, or any mechanics really, but I am prepared to have a bash at this mod in the next couple of months. 5th pops out occasionally, but it is manageable at the moment as it tends to pop on light load, about 60mph when a lorry pulls out in front of me and I back off a bit.

When I rang Sims Toyota, I did ask if there was a synchro or selector fork that went with those gears, but she only gave me the selector fork part number and price. I don't mind buying the fork even if I don't need it just so I have the parts in case I do, but only because it is cheap in the grand scheme.

Do I need to ring Toyota back and ask for more part numbers and prices. What do I need to ask for, I read the howstuffworks.com page on manual boxes (don't laugh) and it does appreciate that different manufacturers implement synchros differently, but I assume Toyota have used a separate cog for the synchro as the HSW site example uses a cone shape between the diff shaft gear and selector collar, suggesting that buying the gear and the collar would be everything needed.

But at least I now understand why there are 2 fifth gears, one for the layshaft and one for the diff shaft.

Anyway, anyone feel free to enlighten me on the Toyota implementation and the potential extra parts that I need to order (get quoted), or provide the info direct if there are any members that work for Toyota.

I can't imagine the synchro parts would add too much more to the overall cost.

Thanks all.

[Clarky_X]

Just rang Sims Toyota again and their system is undergoing an update so couldn't get the details right now, but they should be ringing me back.

What they did tell me is that the synchro parts (rings and springs etc) will most likely be needed as they mesh into the 5th gear and selector fork and would obviously need to fit the output shaft of the AW11 box rather than the donor box.

They estimated the synchro parts were around £30, but I'll update once I've got part numbers and prices confirmed. So it's looking like a £300 mod.

Thinking about the SH box route, another option would be to get a SH box from the corrolla or whatever it's coming from and strip that down for the parts. Not sure how easy those boxes are to come by, but then I may still have the problem of a worn gear popping out.

I'll update later.

[Clarky_X]

So I rang a few motor factors today, none of them could supply any gearbox internals except for genuine parts, which they'd have to go to Toyota for anyway, so it's full price or SH C51 or C53 box only.

Toyota never rang back with the synchro price, so I'll have to chase Monday.

[PW@Woodsport]

I would hazard a guess that the synchro parts won't be needed, but until someone like yourself gives this a try we aren't going to know, so hats off for having the balls to throw a few hundred quid at it

[Clarky_X]

Would it be the synchro that is allowing it to pop out of gear or just the fork? I seem to recall reading on a 5th gear pop out thread somewhere that someone replaced 5th gear and it still popped so they had to replace the synchro.

[PW@Woodsport]

I have never subscribed to the long standing theory that this is a synchro problem, i personally think it is wear on the selector detent assembly or the detent itself to blame.

I haven't investigated it but i probably will now, but i do know these Toyota gearboxes inside out, and if you remove the detent completely it will not stay in any gear, and no part of the 5th gear synchro "keeps it in 5th gear" , its job is simply to slow the two 5th gear cogs to the same speed to allow easy engagement, nothing at all to do with it popping back out.

I can't see how a new synchro assembly will stop it popping out, i think that is an Mr2 internet forum myth, my money's on the detent/selector assembly worn.

[scomr2]

The detents are more to hold the shift fork in the right position when the gear is engaged rather than to actually hold the position of the syncronizer sleeve. This is why you are taught not to hold the gear lever as it overcomes the detent position forcing the fork against the sleeve causing tip wear. The sleeve and the syncro hub have specially shaped grooves that act to keep the sleeve pushed in the right direction to keep the gear engaged. Jumping out of gear is often caused by a combination of worn bearings allowing the shafts to move axially and worn sleeve / hub grooves not holding the sleeve in position.

[PW@Woodsport]

Whilst i agree with what you are saying about bearing wear , i see nothing in the fifth gear assembly or synchro hubs to physically keep it in fifth.... that is the detents job.

[scomr2]

If by detents you are talking about the grooves in the shift fork rods which have a spring loaded ball sitting in them then no their job is to keep the fork positioned in the centre of the sleeve groove - if the detent position was such that the fork was pressing against the sleeve then the fork tips would burn and wear out really quickly. This picture http://www.ae92gts.com/images/tech/tran ... ld/412.jpg shows the detent grooves in the fork rod.

If however you are talking about the sprung inserts in the hub then yes they act to keep the sleeve engaged with the gear. You can just make out the sprung inserts in the hub in this picture: http://www.ae92gts.com/images/tech/tran ... ld/104.jpg

[PW@Woodsport]

Yes i know about the hub spring inserts, but they alone can't be holding it in gear, i have stripped hundreds of these and it is far too easy to slip fifth in and out of the synchro hub, in fact it feels exactly like a "mk1 with popping fith" does minus the detent.

Possibly they both do their jobs hand in hand, but in my experience without the detent (spring/ball) it will fall out of fifth very easily.

[scomr2]

The other part of system that holds it in gear is the way the splines are cut with a minute angle on them so that under torque there is thrust that pulls the sleeve towards the gear. This angle is difficult to measure let alone 'see' and is only apparent when there is torque transfer from the gear through the sleeve and into the hub. When the box is in bits you wont be able to feel the effect because there is no drive torque.

Dog boxes use the same idea - the dogs have a slight taper on them that pulls the dog ring against the gear under the drive torque.

[LimeyMk1]

There's a couple of write ups in the knowledge base on the 5th gear replacement, one by Lauren and one by me.

I found that just replacing the parts covered in Lauren's writeup didn't cure the pop out in my case, I had to change the gear itself due to worn dog teeth (think that's right).

The pics are still there if you have a look.

[Clarky_X]

You beauty, I've been looking for your article for ages, google searches don't show it up and searches using the IMOC search don't either, I've searched for "5th gear" "pop" "fix" all sorts. Zilch. Thanks so much for pointing me to KB. I've been keeping a word doc of all the stuff to do on the car (cos I'm a bit of an anal retard like that) and putting the links to the useful pages against each item, thanks again, I will print it out and use when I get the bottle to part with cash and take the end plate off.

Oh, your pics are there, but Lauren's aren't.

[MartG]

Oh, your pics are there, but Lauren's aren't.

Lauren's article, pics and all, can be found here http://www.mr2.net/trackdayqueen/fithgear.htm

[LimeyMk1]

Another handy link.

http://www.ae92gts.com/ae92gts_trans_rb_1.html

[Clarky_X]

Wow, what a palaver, I’ve been on the phone to Sims Toyota again several times this morning and this time had loads of trouble trying to track the correct parts. Giving them the part numbers that I previously advised, I was told the selector fork didn’t match the other parts, so they had to start looking at what cars the parts matched and then look at other parts that matched that car. It was a long call and the parts lady had to then go off and speak to a technician who was going to look in a manual. Then had to speak to her manager.

Eventually they rang back with the following list of part numbers and prices all for a 1996 Corolla, the gears of which are the same part numbers as the 91 Corolla she was originally looking at.

5th 33036-12170
Synchro 33369-12030
Driven 33428-12110
Fork 33214-12030

293.02 Inc. Quoted for all. Will wait and see what goes on my credit card as that was cheaper than the previous quote.

[PW@Woodsport]

Hats off to you for having the cahunas to have a go at this, i sincerely hope it works out.... the research we did says it will, but you never know until you actually try.

[toxo]

I’ve been on the phone to Sims Toyota again several times this morning and this time had loads of trouble trying to track the correct parts. Giving them the part numbers that I previously advised, I was told the selector fork didn’t match the other parts, so they had to start looking at what cars the parts matched and then look at other parts that matched that car. It was a long call and the parts lady had to then go off and speak to a technician who was going to look in a manual. Then had to speak to her manager.

Sounds like you have found another useful Toyota parts department there! *notes it down* Is that the one at Riverside? Some dealers won't even accept orders for part numbers without having the car's VIN etc...

FYI Toyota in MK are pretty good too, they have imported parts from Japan for me before when they weren't available at the European depot.

[Clarky_X]

Yep, riverside.
Parts in today.
Fitting tomorrow.
Fingers crossed

and it was 293 Inc VAT