My wife is having issues with her S max Dpf filter. We had the filter cleaned but light is back on, thinking of getting it replaced and would like to know how many DPF filters the S Max has (64 plate 2.0 tdci) also can anyone recommend any after market filters as the Ford ones are to expensive 

Before you replace the DPF have you checked to make sure the fuel vaporiser is working correctly?

As above. The cause of a dpf filling up is regen failures. Regen's are reliant on the Fuel vaporiser being able to spray diesel in to the exhaust system, just before the dpf. It basically consists of a glow plug and a fuel feed/nozzle and can fail due to faulty glow plug or blocked nozzle (from carbon build up).  If you keep driving then it will just fill up and I would suggest not driving it if it goes in to limp mode.

Also, I've read in forums that aftermarket dpf's aren't very good and seem to fill up quicker. No experience of this personally though. But my car has occasional dpf regen issues which started in 2017, I replaced the fuel vaporiser and that has generally been working fine except for the occasional failure since I've been driving less during Covid. (error codes suggest that it thinks its electrical connection is unplugged, I reset codes and keep driving and it will eventually regen)

Thank you both for that suggestion will look into getting that changed and see if it solves the issue 

2 hours ago, Olyntus said:

Thank you both for that suggestion will look into getting that changed and see if it solves the issue 

Get it checked to see if it's blocked first before changing it. The fuel pipe removed , fit another pipe on and either blow or suck the pipe to check for blockage. Also the vapouriser has a glow plug with a fused feed. Sometimes the fuse can be blown and stop the regen. Don't get just throwing parts on without knowing what's causing the dpf to fill. 

I think with forscan software it will tell you how many miles since last regen and also you can force a regen. Even if you can’t do work yourself it is handy to have a suitable fault code reader (like the modified Ford one from tunnel rat electronics for about twenty quid ) and forscan software , free for windows, about 6 quid for Apple/android.  Then you can do a bit of checking yourself to see if a garage is taking advantage.

Couple of useful pics