vw transporter unable to reach 120km/h

[David William]

My vw transporter diesel power(auto) is unable to reach 120km/h and on top of that the engine make noisy sound when it almost/trying to reach 100km/h.After it reaches 100km/h the RPM meter is 3500 and it dropped to 2000 when the gear change to top gear.When I accelarate a bit above 2000 than it goes back to gear three and make rough noise again.What seem to be problems? Anybody can help me especially those car owner who have this kind of experience or some mechanical background.?

 

[beardie]

Is it the engine that makes a rough sound or the gearbox. My immeadiate suspision is the auto box but I am no expert. Does the box change cleanly through first and second etc. You dont indicate the miles / service history etc etc. I have heard rumours that the earlier auto box's on T5's are in need of rebuilds / significant rework after 150K ish.

 

[sebking]

Sounds like a 'box issue.

I'd head over to the T5 section on http://www.vwt4forum.co.uk/ and ask the question there