Hi All

I have been on holiday for 2 weeks in the new forest and have done just over 1000 miles during that time. Over the last couple of weeks when driving along i can hear a loudish booming/drumming sound coming form the mid/rear area of the car. The noise only happens when in 5th gear right before the point of if i press the accelerator harder it will change down, or if i raise the revs by about 500 the noise disappears. Only seams to happen in 5th doesn't make any noise in any other gear. Car feels perfect to drive, no performance issues at all in any gear just this weird noise.

Any body any ideas???

Matt

I had the same, sounds as though the sub woofer is cutting in or the rear prop is playing up......... eventually fixed for 1000 miles when I changed the gearbox filter/ oil................then the gearbox:(  5.0 supercharged autobiography
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Matt,

At the time it's making the noise is the rev counter needle rock-steady or is it wavering up and down slightly?

Phil

HI Phil

Its rock steady but happens throughout the rev range but only when in 5th gear e.g. was doing 30mph in 5th at about 1300 revs and its happens as well as doing 60mph at around 1800-2100 revs doesnt seam to matter what the rev is only when im in 5th. If i increase revs (still in 5th) it stops also if i drop to 4th or lower it stops.

Matt

Jonno wrote:

I had the same, sounds as though the sub woofer is cutting in or the rear prop is playing up......... eventually fixed for 1000 miles when I changed the gearbox filter/ oil................then the gearbox:(

happens in manual mode as well when in 5th

i have been reading loads about the LUC on the TC causing the issue between 30-50 mph going to do some tests with it tomorrow and see what the results are and if they are similar to what other people are experiencing.

Matt

ok so i went out today and did some testing on the road.

The Results!

30-40mph low revs around 1300rpm (steady needle) 4 & 5th gear noise happens

50-60mph higher revs around 2000rpm (steady needle) 4 & 5th gear noise happens

noise defiantly still happens in manual mode (4/5 gear) as well as in sport mode

dropping below 30ish mph noise stops, between 40-50mph no noise, accelerate over 60/65mph with increased revs noise stops

noise only appears to happen when transmission is under load e.g. going up an incline. When it happens it feels like its labouring and if i press accelerator slightly harder it will down shift. I must also say that it happens when im driving its with light throttle to maintain revs when it does it, under heavy/hard throttle it doesn't really do it.

Does anyone experience this or has experienced this in the past got any advice. My initial thoughts after doing some research points the issue to the torque converter and its lock up clutch (LUC)

Any additional advice or guidance on how to prove it the TC i would be very grateful.

Matt

Hi Did you ever get to the bottom of his ???

Would be really pleased to hear if you did
cheers

simonevans@me.com