I have a '98 S70 GLT sedan. Previous owner changed the timing belt at about 70K miles. I now have 130K miles. I was thinking the timing belt change interval was 105K miles, but is it actually 70K miles? Should I have it changes again when I get to 140K miles?

On a '98 it's at 70K miles...you are about 10K away for another one. On the second one you need to do the TB tensioner, pulley and dampener too. Also, you should seriously consider a new water pump and WP gasket (when these go, they usually do right before 200K miles- just short of your 3rd change). The Serpentine or service belt and tensioner is also up for a change at 140K miles unless you followed the 60K mile interval for it (no one ever does) and did these earlier. Save your money...it's a bit in parts (www.fcpgroton.com will save you some $$ though). However, labor isn't bad unless you have it all done at a dealer, and you'll buy yourself another 70K miles on the TB (and engine).
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1998 S70 T5 Emarald Green Metallic (125K), 2004 V70 2.5T Ruby Red (45K), Previous Owner of Black '94 850 Turbo Wagon (Sold at 140K and miss her). My cars have been running so well lately they've got me worried.