Shudder in 3rd 1800-2200rpm

[MikkiJayne]

Short of very expensive chemical analysis there's not really any way to tell whats in it, and I've only used genuine fluid so have never seen any red variants of it to compare. The genuine stuff has a distinctive smell too, whereas this red stuff is has no distinguishing features. I'll just re-fill with genuine and go from there.

Its rather odd that the TC was supposedly rebuilt at the same time as the gearbox and has failed after only a couple of years.

[MikkiJayne]

I just opened this second gearbox up to do the filter and re-seal the sump. While there may be red ATF which conforms to the spec, in 100% of two cases, it is indicative of other heinous bodging. In my case, sticking the sump on with bathroom sealant. In this one, forgetting the o-ring on the filter



They also appear to have lost one of the bolts for the filter so used whatever they had kicking around which was much longer than it should be, and did the same on the sump Now I probably have to pull the valve body to make sure the over-size bolt didn't crack it.



Oh, and also the wrong oil in the diffs too. After only 2 years it's as black as treacle so it looks like they used GL4, not GL4+.

[Sit down, Waldo]

This is an old thread to resurrect, but I have these exact symptoms. Seems to happen most frequently when I'm exiting roundabouts, but I think that's just because I'm in the right range. Same in drive or tiptronic. I'd thought it was a wheel / balancing issue tbh.

Mackies had quoted £275.00 + VAT for a full service / flush just before the lockdown started. Any ideas what repairing / replacing the TC is likely to add to that figure? Looks like I might have more re-budgeting to do.

[MikkiJayne]

The converter can be rebuilt - I've had a couple more like this since I made this thread. The TCU attempts to lock up the converter at this rpm range, so the shudder is the lockup clutch failing, either because the friction material has worn (this instance) or glazed (a 6hp), or the clutch piston seals are toast (Big Red). I send them to JP Automatics in Bristol who charge about £400 iirc, to open up the converter, fix whatever needs it, and weld it back together. I did hear a rumour that Mackies are cheaper, but JP are local and have never let me down.

I'm not sure what labour to pull the box, swap the converter and put it back in is likely to be. It should be possible in a day for Mackies since they're used to it, but that would only be with an exchange converter. If they need to recon your converter then probably 2 days elapsed.

I'd guesstimate around £1K total.

[Sit down, Waldo]

Hi MJ, appreciate the heads up. Thank you! But, eeew...not the answer I was hoping for

Factor in the travelling & probably accommodation & that’s an expensive trip. The last trip to pump cost £108 & that receipt is currently stuck on the fridge, so this isn't going to be popular

[Snaggle57]

Mine does this. Its a 3rd car was cheap and I can’t warrant fixing it so just learnt to drive differently to stop it happening. It’s been like this 7 years / 14k miles and has not got any worse in that time. I may be lucky just thought I’d let you know because at first I thought it was game over but it’s not always the case!