xplorr

Thank you for the feedback. I'm glad yours turned out to be the water pump, as it sounds like that is an easier fix than the valley leak.

natehack

Bumping this old thread since I’ll be doing this service soon! Thank you past users for part numbers.

$1450 quote at the dealer was too much to eat. At $240 so far for Aisin pump, Gates belt kit, and Aisin thermostat.

Anyone with torque specs for the water pump?

Beastman

when should I expect to replace water pump and how much could this repair cost.
thanks in advance.
Bill

nuclearn8

I plan to do it at 100k with new radiator, hoses and thermostat. Not sure what parts would cost. Havent looked it up...

Acrad

https://static.nhtsa.gov/odi/tsbs/20...83269-9999.pdf

dubya3232

Just purchase a 2015 gx with 120,000 miles from a local dealer. Car is in great shape for age and mileage. Drove and handled well with no obvious defects. Dealer does a used car inspection and with Lexus reliability record I figured that beyond some typical used car sorting out i would be in good shape for miles to come. Needless to say I get home with the car and discover that the coolant is very low. None in the overflow and low in the radiator as well. This alarmed me and I did some research on this forum and learned about some of the coolant leak issues these trucks can have. I returned to the dealer and we looked over the truck in the lift and could not find the source of the leak. They seemed to brush it off as no big deal. My fear is that I may have a valley plate coolant leak deep in the engine that we may have missed. Are there any other explanations for the low coolant level? Radiator cap ? I have an appointment with Lexus to have an inspection/service and for them to pressure check the coolant system. A small timing cover leak was also found which I was told was not worth the fix and of no harm. Thanks for the help in advance. I am really looking forward to enjoying the truck and not stressing about it.

Manh3

iTrader: (1)

I hope you don’t have a coolant leak or valley plate issue but if you look underneath the truck you should
pink dry spot stains from the coolant leak. I’m assuming the truck is for taking your family around or used as an adventure mobile, I would not go anywhere far until I have the coolant system checked out and corrected because your truck overheating while in the middle of nowhere is not safe.

John00

you can have a very small leak and not be concerned. after a refill of the system, check the tank after a week, then a month, then 3 months so you can know how much is leaking.
maybe the previous owner never ever checked it, so theres 7 or 8 years of loss.
ive had mine about 5 years, and had to add coolant 2 times, each added less than 1/4 qt.
small amount of dried coolant visible when changing the oil, more towards the firewall and back of engine on bottom, not near the radiator.

xychromo

I was concerned about a leak when I first got my truck and have been closely monitoring the fluid level on the expansion tank ever since. Draw a line on the tank at the level of the fluid, when truck is cold, and check that level periodically. Mine hasn't dropped in over 4 months and about 5k miles so I think I'm good for now.

dubya3232

So it has been a week now and the coolant has dropped from full to low. I am returning to the dealership tomorrow to discuss with them. What recourse do I have being the presented the car as inspected when a simple coolant check would have unveiled that there is a major issue going on?

Acrad

Are you able to see anything pink on underbody of vehicle from front to back of engine?

Take a mirror on rear side with a flashlight as well.

dubya3232

I haven’t been able to find any evidence of an external leak. The truck seems to be running well. No rough idle, smoke, oil looks good.

Acrad

How does the oil and coolant look? Can you take some pics?

I'd only pull off radiator cap when completely cooled.

BigLClub

2 types of leaks for the 4.6: Water pump and engine valley.
Info
https://www.google.com/search?q=toyo...hrome&ie=UTF-8
Images:
https://www.google.com/search?q=toyo...w=1396&bih=657

Acrad

Assuming you don't have a head gasket issue you can also check coolant valley with borescope camera.. not 100% coverage but if not leaking over the back may be a better indicator as there could be evaporation before it makes it to the rear of engine.

IMO: Water pump leak on this scale of loss should be really easy to spot.

https://www.clublexus.com/forums/gx-...l#post10922217