Violent judder and loss of drive

[JamieHenderson23]

Bit of a strange one, got one of the last 172 Ph2s made so as I've now learned has a 182 box in it.

For a while its had a tendency to jump out of 3rd and 4th gears when under no load (Dogbone is fine and box isn't moving around.)

Now when accelerating gently in any gear, there's a violent judder that resonates through the car and the revs climb without road speed increasing, doesn't feel like clutch with it being so violent and no smell.

I thought it might have spat a diff circlip so just had the n/s shaft out and turns out it's got a 4 bolt style 182 retainer in so I'd guess it isn't that.

The box oil came out shimmery but no chunks or bits in it that I'd expect to see with stripped gears and seems strange that it happens in every gear.

When on axle stands I can rotate one wheel and the other rotates fine, everything nice and smooth through the diff.

Anything else anyone can think of to check before I pull the box out and see about a refurb or second hand replacement?

Cheers,
Jamie

 

[Louis]

Bit of a strange one, got one of the last 172 Ph2s made so as I've now learned has a 182 box in it.

For a while its had a tendency to jump out of 3rd and 4th gears when under no load (Dogbone is fine and box isn't moving around.)

Now when accelerating gently in any gear, there's a violent judder that resonates through the car and the revs climb without road speed increasing, doesn't feel like clutch with it being so violent and no smell.

I thought it might have spat a diff circlip so just had the n/s shaft out and turns out it's got a 4 bolt style 182 retainer in so I'd guess it isn't that.

The box oil came out shimmery but no chunks or bits in it that I'd expect to see with stripped gears and seems strange that it happens in every gear.

When on axle stands I can rotate one wheel and the other rotates fine, everything nice and smooth through the diff.

Anything else anyone can think of to check before I pull the box out and see about a refurb or second hand replacement?

Cheers,
Jamie

Any movement in balljoints top mounts etc?

 

[Sash]

If the revs are rising but the speed isn’t then surely that’s the clutch slipping.

The judder is likely to be hot spots on the clutch/flywheel I’d have thought.

 

[Louis]

Fair point. Tried shoving it into a high gear and pulling away? Does it slip?

 

[cp1991]

Following as mine does similar, mine is the circlip diff though, lost the circlip the other night, with a proper violent bang, so much it shut the engine off and wouldn't start for 5 minuets. Changed the circlip and restored drive, but try and pull away or with steering, starts knocking loud and violently juddering again. Not even tried to get it in to any other gears, but can pull away with just the clutch fine. Think it's going to be sending the gearbox somewhere to get it looked at.

 

[cp1991]

Prior to the initial circlip failure, had no issues at all with the gearbox

 

[cp1991]

Just an update on mine as it might help, took mine apart again new circlip is already damaged then was greeted by this once the cup part was removed.

Looks like the teeth have stripped off the other side. Might help you out.

 

[NorthloopCup]

Just an update on mine as it might help, took mine apart again new circlip is already damaged then was greeted by this once the cup part was removed.
View attachment 1502406

Looks like the teeth have stripped off the other side. Might help you out.

I see this pretty regular as well tbh. Those bits are happily killing the box if it’s driven. It just becomes a glorified grinder

 

[cp1991]

@NorthloopCup , I'll drop you another DM regarding rebuild later on.

 

[JamieHenderson23]

Cheers lads, so I've managed to get it out and span it over by hand, feels like its not very smooth and knocks constantly. Look like they're hens teeth to get ahold of and Renparts are struggling to get them in. Guess It's rebuild time...

 

[Darren S]

Cheers lads, so I've managed to get it out and span it over by hand, feels like its not very smooth and knocks constantly. Look like they're hens teeth to get ahold of and Renparts are struggling to get them in. Guess It's rebuild time...

If it's rebuild time, then @NorthloopCup above is your man. Worked wonders on getting mine back up to spec!

 

[JamieHenderson23]

If it's rebuild time, then @NorthloopCup above is your man. Worked wonders on getting mine back up to spec!

Cheers mate, everyone speaks highly of his work from what I've seen. Just on getting a quote to get it sent there.