Recently bought a 2005 (2006 Model) 4.4 V8 127k and have noticed the engine revs fluctuate when driving in the 30-50 mph range. Done a far bit of googling and there does not seem to be much about this on L322's but seems to be mentioned quite a lot in Jaguar's with similar engines & same gearbox, all of which point to the torque converter being at fault. It there anyway to confirm what it at fault? If so where is the best place to get one & what sort of job is taking the box out?

Thanks

David

Try cleaning the MAF first. Mine was caked in crud and a liberal spray of Halfords Electrical Contact cleaner did wonders for this. 
07 Supercharged - Still breaking her in!

Boot soundproofing part 1 - http://www.fullfatrr.com/forum/topic15612.html
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Thank you for the reply, that was one of the jobs I did at the weekend, cleaned the MAF & throttle body, which unfortunately has made no difference

I had a chat with a local transmission specialist yesterday and he said try a gearbox reflash first. After that it's probably the TC and you're looking at about £1200 fitted. Not really a job I'd lie to tackle myself personally ... 
07 Supercharged - Still breaking her in!

Boot soundproofing part 1 - http://www.fullfatrr.com/forum/topic15612.html
Custom exhaust - http://www.fullfatrr.com/forum/topic15296.html
18" wheels for Brembo equipped cars - http://www.fullfatrr.com/forum/topic15052.html

I had a TC replaced in Feb and it was £740 fitted at a place in Stoke.