I am pulling my hair out trying to figure out what is going on with the information Bentley is giving me directly, and the information my mechanic is giving me. I am being told form my mechanic that for my car I need 339mm rotors in the rear, that my car with the British Racing Green paint, came with 2 other upgrades one to the engine and one to the brake size which requires 339mm instead of the normal 335mm rotors. I cannot find any information supporting this, he claims he measured them, and contacted (the same dealership I did) and spoke to someone there and they said yes this is correct information. Now when I spoke to the dealership myself, I gave them my VIN number and they are telling me that they cannot tell me the size of rotors but they have them in stock and I can pick them up... My mechanic claims the person he spoke to informed him the 339mm aren't in stock to order so this makes me think the person I spoke with is offering me the 335mm rotors.

Can anyone shed light on this? Did Bentley offer an brake upgrade that changes them from 335mm on the other trims / models to the 339mm mine apparently have? Please if anyone has knowledge, i am all ears because this is getting very frustrating as I cannot source any singular website or parts warehouse that has 339mm for the 2005 Bentley GT or any other year of Bentley GT.

Hello @IMLUCI8 ,
Welcome to 6speedonline !

As to your issue, I think someone is pulling your leg.

You are in Canada, and I take it that your 2005 GT was imported to Canada, or possibly the USA when new, if somehow else acquired, please elaborate.

The 2005 didn't have any special options for the engine, nor with the braking system, the Mulliner package was only an appearance package, so again, nothing to do with the engine or brakes, I am assuming that you have the factory iron brake rotors all around, so your rears would be the 335mm, or 13.18 inches, I would tell your mechanic to measure again.

How long have you owned the vehicle, when were the rotors last changed, and by who ?

Please ask your mechanic to elaborate on the 2 options he claims your vehicle to have.

Johnny

https://www.flyingspares.com/shop/bentley-continental-gt-gtc-cgt-flying-spur-speed/brake-pads-discs/gt-gtc-flying-spur-front-brake-pads-discs.html

The above is a link to Flying Spares. They are a favorite parts source on this forum and located in England. They ship globally. As to your question I am not aware of the rotor differences on the early B....Best ask Flying Spares. Also double check the dimensions of the existing rotors to be sure.

Can you post a picture of a rear disc and caliper?
Is the disc solid or does it have a center plate ( bell) with a ring of bolts.

Also, larger diameter discs also require the calipers moving out by the same amount as the disc diameter has increased. This requires either an adaptor bracket or different bolt position on the calipers or aftermarket calipers ?

Thank you for the response... I am in Canada and from my knowledge the vehicle has always been in Canada. The Mechanic has claimed he spoke to someone at the Bentley here and that is who told him there was some mod from factory that changed the hubs to 339mm... I do not believe this as ALL the information that I gather is that the rear are 335mm and the front are 405mm. I am just nervous to authorize him to put 335mm on the car without knowing for certain that the previous mechanic who did the rotors (don't know who or when) put the wrong size on.

So no pictures then??
I would help clarify a few things.