Hey all. Ended up purchasing an LX470 that was making a little rattle noise last week. It was delivered today, 225k on the clock. I determined it’s making a rattle noise when the heat is tuned on. Was looking it over today and realized the radiator hose was swollen like a balloon after running the heat for about 10 mins. Any ideas on this. Rattle noise seems to be coming from the top/thermostat area but it’s hard to tell.
04 LX470 swollen radiator hose, noise when heat is on
- Thread starter LC CT
- Start date
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Congrats on the new truck!
Coolant circulates through the radiator regardless of whether the interior cabin fan/heat is on or not, so more info is need to pinpoint the noise. Does it make noise at a speed proportional to engine RPM? Vehicle speed? Interior fan speed? A/C compressor engagement/disengagement? Can you hear it outside the truck better or inside? etc.
I'd definitely plan on changing that hose regardless, along with the heater tees and whatever other baseline maintenance the truck might be due for. Timing belt/water pump? Browning radiator? Coolant age? Etc.
Coolant circulates through the radiator regardless of whether the interior cabin fan/heat is on or not, so more info is need to pinpoint the noise. Does it make noise at a speed proportional to engine RPM? Vehicle speed? Interior fan speed? A/C compressor engagement/disengagement? Can you hear it outside the truck better or inside? etc.
I'd definitely plan on changing that hose regardless, along with the heater tees and whatever other baseline maintenance the truck might be due for. Timing belt/water pump? Browning radiator? Coolant age? Etc.
- Thread starter
- #3
Noise is heard from outside the truck, front of engine, nothing heard from inside. I shut the car off when I noticed this hose. I going to get some Toyota coolant soon and a new hose. I didn’t look inside the radiator prior to see the fluid level. I didn’t rev the motor to see if the noise increases or not with it. I didn’t have a helper to do that for me. It is just a lower rpm rattle like noise from the upper front section of the motor it seems. Timing belt was done at 199k from Toyota in Texas. The coolant overflow canister is low on fluid also. I just got the truck this am and just had it running in the driveway prior to noticing this.
Pressure should release into your overflow bottle once it exceeds 16psi. Check to make sure your rad cap is working properly. The way the cap works it's possible for the system to draw coolant from the bottle back into the rad even if the cap is faulty. might explain why the bottle is empty and why you have to much pressure.
In any case it is the easiest thing to check first. Check to make sure there is enough coolant in the system and check the condition of the coolant/rad. Could possibly be a blocked up rad.
What colour is the coolant?
In any case it is the easiest thing to check first. Check to make sure there is enough coolant in the system and check the condition of the coolant/rad. Could possibly be a blocked up rad.
What colour is the coolant?
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Man thats rad hose is crazy. Your temp needle stays in the middle while running?
Failing water pumps on these trucks can produce noises. Do you know more details on the timing belt service at 199? Normally they will replace timing belt water pump, thermostat, all pulleys and serp belt... If it was in fact done at a Toyota dealership, you can plug in your vin on the owners service history site and see exactly what was done.
My thoughts are:
1. timing belt was replaced but cooling system (water pump, radiator cap and thermostat were not) this would explain your noise.
or
2. everything was replaced but wasnt burped correctly causing the hose issue (but doesnt explain the noise).
Failing water pumps on these trucks can produce noises. Do you know more details on the timing belt service at 199? Normally they will replace timing belt water pump, thermostat, all pulleys and serp belt... If it was in fact done at a Toyota dealership, you can plug in your vin on the owners service history site and see exactly what was done.
My thoughts are:
1. timing belt was replaced but cooling system (water pump, radiator cap and thermostat were not) this would explain your noise.
or
2. everything was replaced but wasnt burped correctly causing the hose issue (but doesnt explain the noise).
- Thread starter
- #6
Call to the dealer that had done all the services, they said that the timing belt was done but water pump was not on that day. Would the failing water pump make only make noise when I turn the heat on? When I started the truck cold, there was no noise, ran it for a while, no noise, turned the heat on and noise occurred along with that hose. The dealer is going to email me all the service records they had done on the truck, it’s about 12 years of records I will look through. The needle was half way on the temp mark of the gauge also when it was running. If I swap out the upper hose I’d there anything special I need to do to burp the system? I’m going to do that and then take care of the water pump if I can’t find it done in any of the records. Thanks for the input everyone, greatly appreciated.
- Thread starter
- #7
One more thing I noticed, temps have cooled with hose warm to the touch, hose is definitely soft. Also when I go to squeeze the hose I hear a little creak noise in the intake manifold, similar to the area of the noise when the truck is running making the noise. Should there be any noise from that area associated with squeezing the radiator hose?
- Thread starter
- #9
Damn you’re good, I appreciate that. Is there anything special to do when I replace the upper hose or is it just swap out and then fill the radiator?
That hose is in no way connected to any HVAC related noise IMO, so you likely have at least 2 separate issues.
Also, it is good practice to swap out the water pump with the timing belt. If that was not done, I'd be suspicious that other corners were cut too. And, it is a used complicated car with a lot of miles. So, you probably have more issues than that. IMO, this is a normal part of the purchase process and we've all been through it. Find them, fix them, and be happy.
Going back to your noise:
The A/C compressor is in that general area, and unless you manually turn it off, does often come on even when the heat is on. Turn on the fan/heat, and make sure the A/C compressor is OFF (not on auto). Does it make the noise then, or not?
The Hose:
You DO want to swap that hose, but I suspect you may want to do other cooling system things at the same time depending on the condition of them. Lower hose of the same age? Thermostat? Any browning on the radiator? Heater tees are almost a given. Water pump, if it is leaking or making noise. (this would be all the time the truck is running and proportional to engine speed)
Other stuff:
Fluid condition (oil, trans, xfer case, diffs, brake, AHC), filters (fuel air), plugs, belts/idlers/pulleys, ball joints/tie rods, sway bar/diff bushings, AHC globe condition/pressure-Tbar adjustment, etc etc etc.
Hopefully none of this is news to you.
Also, it is good practice to swap out the water pump with the timing belt. If that was not done, I'd be suspicious that other corners were cut too. And, it is a used complicated car with a lot of miles. So, you probably have more issues than that. IMO, this is a normal part of the purchase process and we've all been through it. Find them, fix them, and be happy.
Going back to your noise:
The A/C compressor is in that general area, and unless you manually turn it off, does often come on even when the heat is on. Turn on the fan/heat, and make sure the A/C compressor is OFF (not on auto). Does it make the noise then, or not?
The Hose:
You DO want to swap that hose, but I suspect you may want to do other cooling system things at the same time depending on the condition of them. Lower hose of the same age? Thermostat? Any browning on the radiator? Heater tees are almost a given. Water pump, if it is leaking or making noise. (this would be all the time the truck is running and proportional to engine speed)
Other stuff:
Fluid condition (oil, trans, xfer case, diffs, brake, AHC), filters (fuel air), plugs, belts/idlers/pulleys, ball joints/tie rods, sway bar/diff bushings, AHC globe condition/pressure-Tbar adjustment, etc etc etc.
Hopefully none of this is news to you.
- Thread starter
- #11
Thanks for the response. It’s not the ac compressor, I had an 03 LC that had a bad compressor and it’s definitely not that. Yes I plan on doing a lot of those things mentioned as the weather allows, i have a set of TRE’s to do also. Then most of the fluids are on my list before I start driving it. the coolant is full in the radiator, was able to check that. Radiator Looks great no browning, where exactly would it start to discolor off it was? Is there anything special I have to do do swap that upper hose or just remove the old and put the new? Then fill the radiator back up? Do I burp the system by squeezing the upper hose and adding to the radiator?
You'll need to burp the system (running the engine with the radiator cap off to allow the air bubbles to exit the system). Do some searching on here to get an idea of the burp process. really straight foward and these trucks usually arent sensitive to the burp process.
If you're just looking to replace that hose then I would:
-completely drain the radiator into a bucket (be sure to inspect the coolant coming out for any plastic or metal fragments and color of coolant for oil mixture
-replace coolant hose
-refill radiator and burp system
-replace radiator cap with a brand new one
I dont think this will solve your noise issue but hopefully it fixes your swollen hose issue.
- Thread starter
- #14
Yes, this will be tomorrow’s project. Got a new radiator hose on. Seems to be ok in that sense now. You only get about 4 hours of Kinda warm in CT these Days. Happy to report AHC works as it should, correct amount of graduations, feels smooth in all heights.
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- #15
Spotless undercarriage. I hope you plan to coat that beauty pronto.
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- #17
I know it’s scary to have in CT. Really terrifying some of the ones I come across up here. Honestly I don’t think I’m going to drive it on wet days up here at all. I plan on fluid filming it and then doing all the baseline, should buy me time til it’s nice in April and no more snow. Going to continue the rust beat down on the 4Runner in the background for winter time
Good idea!
"The dealer is going to email me all the service records they had done on the truck, it’s about 12 years of records"
Have you been on the Lexus owners site to see service history there? It would be interesting to see if Toyota dealers report service for Lexus vehicles to the Lexus owners database.
Have you been on the Lexus owners site to see service history there? It would be interesting to see if Toyota dealers report service for Lexus vehicles to the Lexus owners database.
- Thread starter
- #20
Yes I did. And no Toyota does not report on there unforch. Also you cannot put a Lexus vin In the Toyota system which is a bummer. But the dealership seems great to deal with and took the time to tell some questions I had. I’ll see how many times I have to call to request the records lol but they said it’s no problem.
