So I replaced my radiator (2001 LS430) and when I disconnected the transmission cooling hoses from the old radiator I lost some ATF or whaever it was (dark red). Not a ton I would say but def more than a few drops. Do I need to be concerned about this?

 

If you are low on ATF the dipstick will show it. So check the ATF dipstick - it should show fluid up to the middle of the marked area at its end. Check your manual for specifics. If th estick is low or dry get some Toyota ATF fluid specific for your model year and add a little at a time until dipstick shows fluid at correct level (per your owners manual). Running the ATF low can damage the trans if you lost significant fluid. Doesn't sound like you did but it bears checking as the AT in the LS is a $$$$ part to replace.

 

Thanks for the response, I dont have the owners manual so I'll take a look around online for the dipstick location info.

 

It's near oil dipstick, bit deeper in, but same location.
Drive car for couple of hours, then park on level surface without turning engine off. Put the foot on the brake and go thru all tranny positions (r - n - d and back). Wait 5mins. Pull the stick (car still running!), wipe, reinsert, pull again, check. Should be around middle of HOT section.
Again - level should be checked on driven, hot car, engine must be running, stick in P position.

 

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