The 3 mm id x 9 mm od vacuum hose 007 977 61 82 feels slick on the outside -- like many silicone vacuum hoses. The MBZ hoses is going on 30 years old and looks brand new for the door actuators. I've used non-MBZ vacuum hose only to have they crack within a month.

Is the MBZ hose silicone or silicone modified? Some on the vacuum hoses in the engine compartment show some cracking, but what do I expect after 30 years? I'm thinking of using silicone vacuum hose, but silicone tends to slip more than rubber. I don't want to take apart a door panel to reconnect a slipped hose.

BTW: silicone hoses have 3.2mm id x 2.0 mm wall but the OD is only 6.8 mm. It looks like some round 1.8 mm wall to 2 mm.

On My 84 300D none of the factory Vacuum Hoses appear to be Silicone.

None in the Engine Compartment and none when I was trouble shooting My Door Actuator Leak.

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84 300D, 82 Volvo 244Gl Diesel

Used some silicone hose yesterday on my 300 td. It was left over from a desmog on my landcruiser. The lc guys buy it from Mcmasters Carr company. Very nice stuff, and their online catalogue is very complete. Seems to stay put......

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'85 300 TD wagon. Euro spec. 215,000 miles, real beater (for now). '59 f350 with cummins 6at, 54 gmc flatbed with cummins 6at, '92 f350 service truck with 7.3 NA IDI and 5 spd man tran, Grumman Aluminum stepvan with 6.2 (cabinet hauler) I like diesels.....

Thanks for the replies. I used the CRP 3.5 id x 7.2 mm od white silicone. The ebay silicone 3 x 9 mm hose seem to rip too easy.
Now time to have another try in fixing the truck actuator.