Replacing rear wiper arm

[KMH]

I'm feeling proud of myself for having replaced the two front windscreen wiper arms yesterday - no longer rust coated! But when I tried to remove the arm on the rear screen I couldn't - it seemed stuck fast (yes I did undo the bolt!) and any working of it just caused the rubber seal behind it to begin to pull away and break, so I gave up. I tried WD40 to loosen it, but no change. Does anyone have any advice, please?
Thanks!

[cmm303]

Splines get a bit stiff. I used a puller on mine - to be exact, an old valve spring compressor. (Anything that resembles a G clamp but with a fork at the fixed end to slot behind the wiper. )

[wonkanoby]

http://www.ebay.co.uk/sch/i.html?_from= ... r&_sacat=0

[Simon Jones]

The wiper arm puller (often also described as battery terminal puller) is the safest option. You could try refitting the nut loosely (to protect the threads) & giving the nut a tap with a hammer to break the joint.

[KMH]

That's really helpful, thanks, everyone!

[clutha]

Same happened with me.

I have that 'chiller' aerosol spray, seemed to help after a lot of faff.
Plenty of water proof grease applied on reassembly.

The wiper motor shaft is steel, the arm 'hub is alloy. dis-similar metal corrosion methinks.