Syncro gearbox lifespan

[nrxx]

Thanks everyone. I feel happy now I can make my mind up on something! I just need to decide between Millers (used to use it in my Beesa) and Fuchs that I use now. Cheers Aidan, I'll go the 4ltr route I think.

I wish I was in Oz, instead I'm just a thread hijacker.

Nick

[toomanytoys]

Original poster is in OZ..

dam hijackers........

[eric]

Sorry to butt in lads but I'm having the linkages done next week, after spending about £250 collecting the various kits, flanges, bellows etc., so should I have the gearbox oil changed at the same time?

It hasn't been changed for at least 20,000 mls. I do not know what's in it at present.

The ex-owner of the bus told me (in 2005) when I bought it that ..... "Gear-box was rebuilt by Sinclair's of Swansea and subsequently improved by VW transmission specialist Peter Engesloz (cog-box, London)." I'm guessing this would be around 10/12 years ago.

Any advice is as usual greatly appreciated.

Thanks lads.

Eric.

[KarlT]

For £20 & 30 minutes pissing about, I'd change the oil anyway. You can check how much metal is swilling about in there. That & ease of gear change, gearbox noises will give you a pretty good idea of your box condition, I'd have thought.

Can I join the hijacking.......
As you may of read I'm toying with the idea of EJ25 subaru, but talking about gearbox life-spans has raised, yet again, my fears for my gearbox. So Aidan & others who have seen the inside of, a good many, said boxes, what are your thoughts? Just how strong are they? Compared to a box designed for say 150bhp (subaru one) just how weak & fragil do they look?

[Aidan]

rebuilt with the oiling plates and driven sensibly they are fine, put it this way that's what Yaeger was running in his rally bus uptil he fitted the porsche box, ok it would have had the Weddle/Albins gears in too but he was using it to extreme.
Pete is running a SVXengine with no mods to gearbox other than oiling plates
Russel's and Doug's mTDi and PD engines produces far more grunt than any scooby, they have stronger gears as well as the oiling plates
MG's 2.5 TDi runs oiling plates now, first 30k without them showed they were needed.
I give the same warranty too the alt engine boys as the standard ones

[eric]

Nice advice to Karl, Aidan, now could you recommend what oil I should use for my Syncro?
8000 undulating Welsh miles per year ...approx. Mostly on tarmac roads, but some off-roading like the fabled `Sarn Helen` Roman road sometime after 1st June.

Thanks mate.

Eric.

[Aidan]

as above and in a multitude of other replies
I should get shares in Fuchs

[syncropaddy]

Aidan will probably have something to say but the only time I have ever put fresh oil in a gearbox was when I got mine back from refurb.
I have covered some high mileage in various cars over the years and I never changed the diff oil or gearbox oil, ever. One particular car, a manual Mercedes 200TE, I covered 274,000 miles in it before I sold it. I met its owner recently and he told me that its covered 420,000 with the same gearbox but different engine. All of my old Jettas covered a minimum of 150,000 and none had the gearbox oil changed.

So why are we all changing our gearbox oil?

[Aidan]

cos if you don't it looses lubricant qualities and builds up fines and turns to grinding paste, since our gears run on needle bearings that run directly on the shafts this can result in damage to very expensive bits of kit
you change the oil in the engine every six months; apart from products of combustion what's the difference, they both get hot and it's fair to say our box is at the performance limit temperature and load wise, anything more modern doing what ours does either has an oil pump/cooler/filter or a short design life, lets face it most cars these days don't see 10 years or 150k miles as they are taken off the road by emmisions regs, we are driving one of the last vehicles that can be kept on the road for longer than it's intended lifespan.
Over half the boxes I've rebuilt have been rebuilt before and seeing the wear on the internal components day in day out leads me to recommend frequent oil changes, as I've seen boxes that have clearly been oil changed that do 300k miles with little wear and I've seen ones that are shagged at 30k with no oil change and long periods of inactivity
oil is cheap
a rebuild isn't, especially if it's been put off

[syncrosimon]

I can remember the VW technicians telling my dad that checking the gearbox oil was not a service option as they were sealed for life.

It's just a feel good factor I suppose. I think once a year is fine for engine oil. My syncro had it's gearbox oil changed yearly, but it still wore out the 3rd gear syhchro hub.
How the vehicle is driven is probably more important.

It's now done 81,000 miles and is making some whining noises now

Got a thousand mile trip at Easter, so we will see if I need Aidan after that, kill or cure.

[syncropaddy]

cos if you don't it looses lubricant qualities and builds up fines and turns to grinding paste, since our gears run on needle bearings that run directly on the shafts this can result in damage to very expensive bits of kit
you change the oil in the engine every six months; apart from products of combustion what's the difference, they both get hot and it's fair to say our box is at the performance limit temperature and load wise, anything more modern doing what ours does either has an oil pump/cooler/filter or a short design life, lets face it most cars these days don't see 10 years or 150k miles as they are taken off the road by emmisions regs, we are driving one of the last vehicles that can be kept on the road for longer than it's intended lifespan.
Over half the boxes I've rebuilt have been rebuilt before and seeing the wear on the internal components day in day out leads me to recommend frequent oil changes, as I've seen boxes that have clearly been oil changed that do 300k miles with little wear and I've seen ones that are shagged at 30k with no oil change and long periods of inactivity
oil is cheap
a rebuild isn't, especially if it's been put off

See ....... I told you he would have something to say

Well the Jettas all ran needle bearings and so did the Merc and 'sealed for life' was a buzz phrase in those days. I'm talking about the late 70's and early 80's and oil coolers and filters on the gearboxes were not in the equation. I'm talking of the days when IBM made typewriters and synthetic was a man made fibre. I'm talking of the days when the Syncro gearbox was designed ......... to the standards of the day.

Don't forget that in Germany, cars were designed and developed by the manufacturer to pound up and down the Autobahns all day, every day and they did it without issues and 300,000 kms was common then as it is now. That cant be said for too many other countries car manufacturers. So with that said, why are we changing the gearbox oil?

[toomanytoys]

My subaru has a 30k service schedule for the gear and diff oils.......... maybe I should ignore it then....

I'd say the T25 gearbox is a marginal design.. there are a few "features" about them that dont make sense... (special bearings half way between std available sizes, coz the smaller one wasnt good enough and no room to fit the bigger one..) and the 5 speed has always been considered weaker than the 4 speed...

just because some types of gearboxes will do 300k on the same oil doesnt mean others will too... should we do a full design review of Jetta/merc/T25 gearboxes to find out why?? Frell off.. I'd rather spend £20 and 20 mins to know its as good as it can be...

[jebiga41]

some sound medical advice prevention is better than cure.

cos if you don't it looses lubricant qualities and builds up fines and turns to grinding paste,

Andrew you must be one of the few that likes sand in their vaseline

[toomanytoys]

some sound medical advice prevention is better than cure.

Andrew you must be one of the few that likes sand in their vaseline

[syncropaddy]

some sound medical advice prevention is better than cure.

cos if you don't it looses lubricant qualities and builds up fines and turns to grinding paste,

Andrew you must be one of the few that likes sand in their vaseline

That's the second time you've said that Paul ....... You know I dont like vaseline