When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Long time visitor, and first time user. I have a 3rd generation truck that started making this noise during our first cold snap in Columbus about 1 month ago. Here is a Youtube video link to the engine and sound.... It is titled:
1. All 3 belts are fairly new
2. The A/C idler pulley was replaced 9 months ago.
3. The alternator is brand new
4. The power steering pump is not the culprit - verified by Toyota mechanic.
5. It only does this on very cold days (we have had a lot of them), and ususally after truck has been sitting and engine is cold.
6. The timing belt, water pump, tensioners, etc. were replaced 30K miles ago.
I think it may be the a/c idler pulley again? (I used the Gates 38031, so it should be OEM quality)
I am thinking it could be the fan cooling bracket?
I have a stethoscope, but cannot totally pinpoint the noise. Any help/suggestions would be greatly appreciated!
Thanks for the response, Wyoming9. The noise is present either with the defroster on or off. Like you, this typically happens only when the temperature is below 10 degrees. I really can't pinpoint the sound to the a/c idler pulley or fan bracket mount. I do know when I listened under the truck, it seemed a little louder underneath - maybe the a/c idler pulley, since it so low on the engine??
I wish I could hear a bad fan bracket mount, so I knew what it sounded like.
Hey Buoni,
Were you able to figure out the source of the screeching noise?
I had what I think was a similar screech last winter that went away when the weather warmed up.
Now that it's down to the single digits it has reared it's ugly head again!
Sounds like the exact same sound. Here is what I learned last year. I replaced the alternator, as there was "noise" that came from it when I used a long-handled screwdriver. However, two weeks later, the noise came back. I ended up replacing all three drive belts, and the A/C Idler Pulley with Toyota OEM parts. The noise went away. I had newer belts and a 9 month old Gates A/C Idler Pulley, but the noise came back when it got really cold. When I put the Toyota OEM belts and Idler Pulley on, the noise did not return. It's in the single digits here, and so far, so good.
As a last note, here is the A/C Idler Pulley I actually ordered.. it is Toyota Part # 8844035060
Make sure the belts are Toyota Belts as well. Even though there are good quality OEM quality belts, I swear these OEM's are quieter -- they almost have a slight felt-like texture on the back.
Anyway, this has solved my problem thus far.
Would love to know if this works for you... Good luck,
Thanks for the reply!
This all makes sense as I have been chasing the sound from the topside. It sounded more like a whistling noise to me, so I thought I was hunting a vacuum leak. And hell, nobody wants to drop the skid plates outside in the dark when it's 2 degrees with a 20 mph wind!
I did go back out in the dark last night and was able to do the broomstick/ear test. Definitely loudest in the A/C area, but missed the idler pulley as it's really low and tough to spot from above.
3 years/45K miles ago I used the aircabinman kit and changed all belts and pulleys with Toyota parts EXCEPT the drive belt idler pulley as that was not included. So I purchased, you guessed it, the Gates 38031 replacement from Rockauto!
Thanks for the Toyota part number! I'll try to track one down asap and swap it out. Then do the belts as regular maintenance on a warmer day.
Yep... I had the Gates in there at first... It seems like a good idler pulley... The Toyota one I mentioned comes with a new bolt and dust cover in the front. That idler pulley is definitely a PITA, but you should be able to replace w/o removing the plate. I order from Camelback Toyota Parts... think it runs around $40... good luck.
Thanks for the info.
I just ordered the pulley on eBay from genuinetoyota for $45 incl. shipping. They are close by in Wisconsin and I needed to have it by the weekend.
Also ordered the 3 belts from aircabinman for $58.55.
I suppose to be safe, I could just cut off the A/C belt now. I'd hate to lose the other two belts(or worse) if the pulley seizes and the belt jumps off.
I've been helping a friend move so I can't just let it sit.
Saturday is supposed to be a sunny, almost tropical 32 deg!!
Assuming the parts get here I hope to tackle it then.
Awesome. Your rig looks pretty nice from the profile pic by the way. I hope this cures the issue for you. We just experienced our first single digit mornings with below zero wind chills. When I replaced the pulley in early March 2015, it started to warm up, so I never was certain if the noise was 100% fixed. So far, so good, though. My next step would have been to look at pulley on the actual a/c compressor, but don't fix what ain't broke. LOL.... Good look, man... Look forward to hearing how it goes.
Thanks for the complement!
I had always wanted a 4Runner and I really lucked out getting this truck. It was the cleanest one I could afford. I did all the maintenance stuff first, TB, hoses, gaskets, radiator, shocks, big brakes then worked on making it ride smooth and quiet. As much as I appreciate a trail/expedition/zombie apocalypse prepared monster truck, that's just not where my life is right now. My reality is we take a lot of road trips to Michigan and the truck spends 99.9% on pavement. So I added the Airlift 1000, lots of sound deadening and the 17" FJ wheels and tires. Rides smooth, tows straight and is a beast in the snow/slush.
When it's clean, people can't believe it's a 13 year old truck with over 200K miles. One of the biggest challenges continues to be the salt/brine mix they use on the roads these days. REAL nasty aggressive stuff.
Back to the task at hand! I'm grateful that we're leaning towards the pulley and not the compressor. I'll report back and let you know how it goes.
Here's another shot on a clean day. Can you tell I love this damn truck?
She's a beaut, and I am in the same boat as you. I've done the same exact things you mentioned, so I'll have to share a pic when I get a moment. I put Bilstein's on, and put a new set of the TRD snowflake wheels on that you usually see on Taco's around here. I put new radiator, hoses, belts, TB, Tundra brake upgrade (used Brembo blanks and Akebono ceramics), etc., etc. I just did lower ball joints this past weekend w/ Toyota OEM's -- next is a swap out on one of my Universal joints... Great rig -- I am approaching 200K on mine, and it honestly drives better than most newer things I have ridden in.
Hey Buoni!
As soon as the parts showed up last week, the temps warmed up into the 20's and 30's and the noise went away. But MY cold came back.
Waited til today to replace the pulley since the snow is gone, it's in the 40's and I'm feeling much better.
I drove it up on ramps and dropped the skid plates for access from underneath. Real easy to remove the nut with a 14MM socket on a long handled ratchet.
It's a tight fit for the adjuster bolt, so I used a 14MM stubby ratcheting combo wrench.
No screeching with the new pulley! The 3 yr. old Gates pulley sounds a little rough, so I did an experiment and put it in the freezer for a bit.
Sounds real bad when I spin it while cold. I'll try to post a follow up vid with the frosty cold Gates pulley.
I'll replace all 3 belts in the Spring when I have more time.
Thanks again for your help!
3 yr. old Gates AC Idler Pulley assembly compared to new Toyota part. Also showing adjustment bolt in the middle of the pic.
Looking up from below. AC Compressor is upper left. Crank pulley is upper right. Belt adjustment bolt is below AC Idler pulley at about 5 o'clock.
Inexpensive stubby ratcheting combo wrench set from HF.
02-24-2015, 08:34 AM
