Our 2004 Hyundai Santa Fe with the 2.7L V6 and auto transmission has been a great car for us, with 230,000 miles of almost exclusively high-speed driving so far and no major problems. But now it won’t shift out of 2nd gear. One mechanic we know says it might be a sensor problem, another says it is b…

Don’t replace parts blindly. Go to a dealer and get the error codes read. Post them here. "we’ve been told it could do more harm than good replacing the fluid after 100K" That’s an old myth. Can it accelerate strongly when in 2nd gear? That would rule out a plugged converter.

Every time I have been to a mechanic that can figure something out - catalytic conv.

We’re going to get the codes read when the dealer opens tomorrow. Sounds like changing the fluid might be the first step to see if that helps. Is it worthwhile to pay more for one of those transmission flushes where they circulate the fluid in and out several times, or is just draining the case and …

You can have them do that “flush” thing, but it’s really just a fluid exchange. That would be fine, although more expensive than a drain/fill. It also changes more of the fluid. Regardless of which way you go, check the difference between the old brown nasty stuff coming out, and the nice pink, cle…

Error codes dont mean a damn thing if you cant/dont diagnose them

Apostrophes don’t mean a damn thing if you can’t/don’t use them. (periods too)

“We also have never replaced the fluid because we’ve been told it could do more harm than good replacing the fluid after 100K.” Sounds like the transmission is on the way out due to never having changed the fluid. What you were told per the comment above is total bunk.

Can a cat converter cause transmission problems?

Maintenance/Repairs

chaissos June 6, 2011, 1:04am 3

If it hasn’t been changed in that long, change it, and then change it again in 1000 miles or so. It may require a third change to clear out some of the muck that’s built up. Don’t believe the myth - I don’t anymore.

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Can a cat converter cause transmission problems?

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