My 2010 LS460 L is slowly losing coolant . It started with my heater not giving heat. Took it into a private Lexus mechanic and couldnt find any leaks. Says it was most likely in the engine and I should probably get rid of car. I hate to do that because it really runs great other than that. I have 108000 miles on car. Does anyone have suggestions that wont cost an arm and a leg. Thanks

 

if you see no leaks at the top, where the hoses connect or where the plastic crimps onto the metal it is at the top of the radiator, you see no crusting pink powder... fill it up again with cheap compatible coolant in the US you can get aisin pink coolant for very little money... you can also check your coolant tank to see if any oil seeped into the coolant system and you can also buy a cheap tester to test the coolant to see if any engine and exhaust chemicals are in there. and check you dipstick for any signs of liquid and coolant.

 

also check for a hidden accumulation somewhere around the valley plate? Read that somewhere in the forums

here a link to one thread

https://www.clublexus.com/forums/ls-...late-leak.html

 

I'd check the corners of the radiator, it can be very difficult to catch a radiator when it seeps out of the corners. Pressure test may not show anything. So get a flashlight and look for pink staining on the radiator sides. If you see anything, that's your leak.

If you had a blown head gasket youd be getting some misfires, you'd be overheating. Coolant would be bubbling in the reservoir. You'd be getting white smoke out of the tailpipe consistently.

 

I think you should find a new mechanic.

 

What do you mean by slow? It needs more coolant every day, week, month, year? These cars have an incredibly small coolant reservoir. I need to add coolant to mine every 6 months. I put about a pint in and it’s fine. I can’t find any sign of a leak.

 

Adequately tightening the reservoir cap is important - tighten it until it “clicks.”

 

The plastic end tanks on the radiator are probably cracked somewhere. I just replaced my radiator Saturday. Last week I changed the belt, and the nipple to the overflow snapped off because it was so brittle from age. It had crust around the edges as mentioned above before this snapped though so was already leaking. it is a PITA to change btw. The AC condenser is bolted to the radiator. You have to pull the lower plastic panel to reach the 2 lower bolts, and disconnect the lower radiator and transmission cooler hoses. Then on the top, you have to pull the intake pipes, unbolt the upper radiator support so you can move it enough to remove the top 2 bolts holding the condenser to the radiator, pull the reservoir, and be sure you disconnect the hose from the engine first. Pull the upper radiator hose, Pinch the 3 top clips that hold the fan assembly to the radiator.Push the top of the fans toward the engine ,and then lift it slightly to free the lower portion and ull them out after disconnecting the wires. THEN the radiator can be finagled out. They really designed this car to make you take it to the dealer for everything.

 

I just got back from an independent mechanic. He did a pressure check and said there was some seepage from intake manifold and it would cost at least $700 to pull it off and inspect.

 

I’ve got an 11 GS 350 with only 76500 and began smelling antifreeze a few months ago or so. Checked coolant ants saw the reservoir went from full to low over a 2-4 week period. Put the car on a rack looked and looked was never able to find anything. Just this week I had it out to my mechanic and he found the leak coming from passengers side head gasket. I am beside myself and now stuck trying to figure out what to do. Seems ridiculous that a Lexus with so few miles would be experiencing this.

 

I had a slow coolant leak on our 2013 LS 460. The coolant needed refilling every few days but was hard to detect any leaks and no drips on the ground due to the underbody panels catching the drips. It is detailed here and was $570 total for my mechanic to diagnose and fix. Hope the photos help you locate the leak.

Our 2006 LS 430 also had a very slow coolant leak due to a different, but common, issue -- radiator cracks.

 

My 2008 LS had a slow leak that I just had to top it off once a year. It started around 100,000 miles but never got worse than having to top it off once a year. My 2017 BMW is doing the same thing at only 30,000 miles.