I just bought a used LS400 (1990 w/ 175K mi) and just before I bought it I researched and found out its one of THEE most reliable cars EVER built.

I also own 2001 IS300 (bought new) that now has 78K mi and in mint condition.

Thinking about selling the IS to get a used SC430 for about $30K, with about the same amount of miles as the IS and probably around year 2003.

What would be the order of reliabililty of the 3? Expected milage each one would give me before it wouldn't be worth fixing anymore?

Thanks in advance!

 

There are many threads on this here but to summarize the SC430 is about as reliable as your going to get period. Rated most reliable for a few years in a row. Early models had a couple of hiccups but nothing serious.
Mine has been very trouble free and a joy to own.

 

I have a 2002 sc430 now and it really has the same feel as its predecessor the sc400. I had 2 1992 Sc400's. One I took over 300k miles and the other I took over 400k miles. Neither had any major problems, never had the engines rebuilt, trannys lasted the whole time. Pretty much the only maintenance was general scheduled maintenance. Both ran great with very little issues the day I sold them.

I expect the same out of my SC430. They are well built cars and if you take care of them, you probably won't find a more reliable car.