I am looking to get some 20" alloys for my e60 530d. I currently have runflat tyres on the standard msport wheels, but it seems like most people advise to use non-runflat tyres and to go with slightly oversized tyre sizes of 245/35/20 and 275/30/20 rear. (to retain some comfort)

My question is; will I be able to fit a space saver spare (fitted with the correct tyre size to match the new overall diameter of the 20" wheels) in the boot compartment?

 

The diameter of 275/30/20 is 26.5" if that will help. But, I think it's too big.

 

The spacesaver with a 19" setup is a tight fit ,and is 1" smaller in diameter than the 20" tyres.

 

Just because the 19" rim is 1 inch smaller than the 20" rim does not mean the overall diameter is different. My spare is the same diameter as my 18" and my 19". You need to check the diameter and if they are same or close you should not have an issue. Remember if you don't have an Xi it should not be an issue since there is not LSD in these cars. Plus if it is an emergency a slightly different diameter will not cause damage.

 

I think that you have missed the fact that the proposed 20" tyres have exactly the same profiles as a 19" setup and are therefore 1" larger in diameter.In order to retain the correct diameter the OP would have to use lower profile 20" tyres.

 

That's correct. The correct tires are 245/30/20F 275/25/20R, but most use 245/35/20F 275/30/20R for extra rim protection and comfort.

 

 

Thanks for all of your replies, I will measure the space for the spare wheel.
Is there anyone on here running this wheel setup? Would tyre foam/sealant be a suitable substitute for a spare wheel?