help! bits in gearbox oil

[Royden]

hi. im new to this so do point it out if im doing this all wrong. i have just bought my first t25. im in need of a bit of advice. i changed my gearbox oil yesterday. first time in at least 10 years i reckon, talking to the bloke i bought it from. the oil was filthy and there was a lot of bits of metal on the magnet. it looked to me like bits of a needle/roller bearing. the box was noisy while driving and reverse was a nightmare to find. i have put fresh oil in it and to be honest it seems quieter and reverse was easier to find if i doubled the clutch. what i need advice on is what to do next. is this a common problem? does it sound like the box is going to explode at any minute? can i risk using it until i can afford a reconditioned box? whats the worst that could happen? basically as this is my first van im a bit clueless on this one. any advice would be gratefully accepted. thanks. royden

[AdrianC]

what i need advice on is what to do next.

Drive it.

does it sound like the box is going to explode at any minute?

No.

We changed the box oil on ours about 30k miles ago. I don't know how long it'd been since it was last done, but the drain plug was thoroughly corroded in place. A LOOOONG while. If ever. The drain plug looked like an Xmas tree. It's what happens over time, with changes ignored.

[Royden]

thanks for the reassurance Adrian. there was what seemed to be a complete roller or needle from a bearing, but just the one. does that suggest a bust bearing or could that again have been historic?

[CJH]

The christmas tree effect looks worse than it is. I bought a second hand box, condition unknown, as a stop-gap while my own box is being reconditioned. The seller drained the oil from the second hand box in front of me, so I could get a clue as to the internal condition. The drain plug was quite furry, and looked like it was covered in coarse iron filings. But when I attempted to pinch some between my fingers they disappeared - I think they were so fine that only being suspended in oil on a magnet gave them any visible structure. The box proved to be fine, with only a worn 3rd gear syncro 'crunch' to worry about.

I'd be concerned if there were distinct chunks of metal on the plug though.

[Oldiebut goodie]

But he states that there appears to be a portion of a roller bearing - that is completely different to having particles on the plug. It is more serious than you both ^^^^ are saying. Aiden will say the same I should think.

[CJH]

I agree - that was the point of my last sentence. I'd be concerned.

[itchyfeet]

yes i'd agree bits of swarf are one thing, bits of bearing are quite another, i'd be lookng out for a second hand box and then get Aidan to rebuild at leisure (as he always has a waiting list) then sell the second hand box.

this was the christmas tree from my gearbox which Aidan has just rebuilt, he said it wasn't that bad, no whines or crunches just hard to get in 1st and second so this is probably typical but bits of bearing surely means trouble ahead.

[CJH]

yes i'd agree bits of swarf are one thing, bits of bearing are quite another, i'd be lookng out for a second hand box and then get Aidan to rebuild at leisure (as he always has a waiting list) then sell the second hand box.

I did just this when I found a bit of the 3rd gear syncro hub on my drain plug! This was before I was aware of Aidan though, so I've used a local guy. My 'stop-gap' 4-speed will be up for sale in a couple of weeks time, when my rebuilt original goes back in. Perfectly serviceable provided you don't mind a bit of crunching into 3rd (from either direction).

[itchyfeet]

OP is a diesel yours ^^is petrol

[CJH]

OP is a diesel yours ^^is petrol

Oh. Hadn't spotted that.

[Royden]

Thanks for the thought though. Looks like I'm looking for the gearbox then. Do you all think that driving it is a mistake?

[AdrianC]

But he states that there appears to be a portion of a roller bearing

Yes, that bit makes a difference...

[itchyfeet]

Thanks for the thought though. Looks like I'm looking for the gearbox then. Do you all think that driving it is a mistake?

I'd say you will be OK driving it short term but I wouldn't go on a long trip with it. Stop driving if it starts deteriorating.

may want to invest in breakdown cover

[AdrianC]

The more I think about this... that roller hasn't been in service for a while. It's not the oil change which has got it out of place. If anything, the oil change has _prevented_ that loose roller from getting where it shouldn't be, not to mention the benefits of everything running in shiny new slippery oil instead of black grit.

How long has it been displaced, anyway? Nobody knows. Tens of miles? Hundreds? Thousands? Tens of thousands?

So why should the _knowledge_ that a bearing's disintegrating cause us all to be so suddenly wary of driving the van much?

[Aidan]

If it's a five speed then the roller will be from either 1st gear or the end case bearing which has(maybe both have) collapsed due to a worn pinion bearing allowing the pinion shaft to move forward under load compressing the 1st gear between the end case thrust bearing and the synchro hub and the difficulty getting reverse is down to the same cause. Figure on a grand plus rebuild if I'm right
If it's a four speed then it's probably the same cause but reverse gear needle bearing has collapsed following damage to the thrust washer (which is plastic) behind reverse gear
If the needle is only 4mm long and 1mm dia that's the thrust bearing, if it's 3-3.5mm thick then it's either a gear or shaft bearing.
Currently booked till end of October


Itchyfeet I haven't forgotten/ignoring you, just extremely busy, will be back in touch next week, got to finish an engine installation away from base this weekend.