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yeh keep the thread updated, should be a good box once done.

There's your problem. 2-4 band anchor point for the pin failed. Instant loss of 2nd & 4th gears.
Day started badly.

Trying to remove the bellhousing, which has to be done as the pump won't come out with it attached, resulted in 1 rounded bolt and only 2 of the 8 bolts coming out with my rattle gun set to MAX. Oh My Goodness, these are tight. Using an impact driver and maximum poundage with a stoning hammer (mini sledge hammer) resulted in 2 more bolts coming out. The remaining 4 bolts required a punch, and some not-so-gentle persuading with the stoning hammer in an anticlockwise direction, and I finally managed to get the remaining 4 bolts out. Bolts were FUBAR by the time I finished.
Once the pump was out, everything else went by the book with no further hiccups.

What I discovered once the transmission was disassembled was that all the frictions and rubbers are in excellent condition. No hardening of the rubber O rings what-so-ever. Nothing like what you would expect after 250k of use. Also, when removing the transmission from the car, 1 of the bolts holding the trans to the engine was missing, and I very much doubt it left the factory with a missing bolt. These facts lead me to believe that the box may have already been rebuilt, and not so long ago. So what I would like to know is, would it be wrong of me to simply replace the 2-4 band, as well as the pump & extension housing gaskets as they got destroyed during disassembly, and reassemble it using the existing clutches? It would save Junior a couple of hundred bucks, and I can't see the point in replacing what seem to be perfectly good, operational components. Opinions?

And, assuming it was rebuilt, could the failure of the 2-4 band anchor point be attributed to faulty assembly? If so, what may have caused it as I'd hate to make the same mistake.

Anyway, this is where we're at by the end of today.

wow anchor point fail wouldn't have guessed that, was guessing the servo pin point, i know the anchor pin should go down into the case not be level with the top from memory, so if it wasn't pushed all the way in or the band wasn't installed properly it could be possible. If the box was factory then by 240k unless it had alot of oil changes id expect the last clutch in the 4th to be a bit worn from what i saw doing mine. Those hex bolts are a PIA no idea why they wouldn't just use normal studs, check the pistons if you have them out for cracks and check the sunshell around the gear ring those normally cop it.

The1 wrote:wow anchor point fail wouldn't have guessed that, was guessing the servo pin point, i know the anchor pin should go down into the case not be level with the top from memory, so if it wasn't pushed all the way in or the band wasn't installed properly it could be possible. If the box was factory then by 240k unless it had alot of oil changes id expect the last clutch in the 4th to be a bit worn from what i saw doing mine.

Oil was filthy when I drained it, and that was after a service with 5L of fresh oil, so if the previous owner did do regular oil changes he must have really slackened off near the end. I'll have a closer look at the last clutch in the 4th tomorrow. In the VP Calais transmission I rebuilt after 250K I found that the rubbers on the forward clutch housing & low and reverse clutch piston had no give whatsoever, whereas this transmission they're still really good. That's why I'm thinking that it has been rebuilt not so long ago.

The1 wrote:check the pistons if you have them out for cracks and check the sunshell around the gear ring those normally cop it.

Will be doing all the checking tomorrow. Didn't get around to checking in detail today. Ran out of time.

On another note, Junior has just asked me a question. He'd like to know if axle tramp could have caused the band to rip out? The plot thickens.

If the transmission had been rebuilt already I'd suggest it was a faulty part that just let go.
Can axle tramp to that? anything is possible but I doubt a drive wheel bouncing in place after losing traction would be the cause of the issue.

Replace the band and put it back together, the money he saves there can be spent on some decent shocks for the rear to stop that axle tramp

Looking at the failure my guess is the anchor pin was not all the way in. It wasn't holding the band just the protruding boss. A tip that would have saved some grief undoing those tight bolts. Using a soft drift and a big hammer smack the bolts hard directly on the end. A few hard hits and they will be much easier to undo.

def sounding like it's been rebuilt, if clutch is good and hard parts look ok then id replace band and reassemble.

Charlescrown wrote:Looking at the failure my guess is the anchor pin was not all the way in. It wasn't holding the band just the protruding boss.

That's exactly what I was thinking, and if that is the case, then it must have been rebuilt, as I don't see how it would have taken 250K to fail. Surely if it was incorrectly installed in 2003, it would have let go much sooner, and not by a motor that has 250K on the clock and obviously nowhere near as powerful as a fresh motor.

Charlescrown wrote:A tip that would have saved some grief undoing those tight bolts. Using a soft drift and a big hammer smack the bolts hard directly on the end. A few hard hits and they will be much easier to undo.

Smacking the absolute shit out of my impact driver with the stoning hammer pretty much did just that. By the time I'd finished, the smacking end of the impact driver had flared considerably, so rest assured, there was nothing gentle about it.

The1 wrote:def sounding like it's been rebuilt, if clutch is good and hard parts look ok then id replace band and reassemble.

Yep, that's exactly what I'll be doing. There is no way this box has taken 14 years & 250K to fail the way it did. The evidence is overwhelming. The box has been rebuilt and whoever did the work failed to insert the 2-4 band anchor pin as deep as he/she should have. I will not be making the same mistake.

Chuff

I guess the question about the axle tramp would be a matter of it probably was the cause if that was the time the gearbox failed .... that said I agree, its ripped just the boss off like it was never right in, so it was probably never going to hold as much as it should have.