I would say the difference the tires are going to make is going to be well
worth the money.  I had a customer's Westie here with car tires on it.  The
van was low miles and everything was tight, but when you went around corners
you could feel the tires giving and they actually would squeal a bit when you
would take a turn slowly.
I replaced the shocks on my van (with new Boges) thinking that this was why
my van was riding terrible.  The shocks helped a little but the van still was
riding crappy.  I invested in some new tires (to go on my 15" rims) that were
light truck rated, and I noticed a world of difference.  So in bang for the
buck the tires actually are a better investment than the shocks (those Boges
didn't seem to really be worn out anyway, even after 150k miles!)
Hope this helps.

Thanks,
Ken Wilford
http://www.vanagain.com
John 3:16

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