New OEM fan clutch but still roaring dump truck? (1 Viewer)

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Joined
Jun 6, 2022
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Location
Arizona
Hi! A few months ago I sold my V8 4Runner and bought a 2007 LX470 with 87k miles. It had a roar that corresponded to engine rpm. Usually this would be the result of a locked up fan clutch. Last week I got a new OEM fan clutch (could have gotten and Aisin from Amazon I know) and installed it. I thought for sure that the roaring would be gone, but it didn’t! Still sounds like a large dump truck rolling down the street! The fan did not and does not wobble or have chirping or clicking sounds like bearing failures would cause. During removal, one of the four bolts did come off as I was fighting to get that nut off. But everything installed back right and fine. Any thoughts?

Also I understand a locked up fan clutch would cause dropped mpg and engine power. I get a pathetic 12 mpg. But would it affect shifting too?? The transmission seems to not like going into overdrive, especially climbs or sometimes even on flats. It would maintain high rpm when I expect it to get to a higher gear and drop rpm. Sometimes it feels like the gas pedal doesn’t want to go down and the engine rpm struggles to climb and deliver torque. I’d owned the 4Runner with the same engine and transmission for 14 years and driven plenty of mountain roads. It behaved completely differently - a lot smoother. I should probably post about the transmission in a separate thread. But wonder whether the fan clutch could cause the feeling of transmission problem?

Thanks all. Insights will be appreciated

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My fan clutch is about to go, but I have not noticed my transmission acting up. There are a few tricks to check your fan though...

When is engine is cold and off, it should be easy to spin the fan. And once engine is on and at operating temp, a bundled up newspaper should be able to stop the fan.

If your clutch is of the blue variety then the 80s forum has a write up to replace the silicon fluid which is only ~$10 per bottle from a specialty shop. There are different viscosities to choose from depending on what part of the country you’re in. I decided on the 7k here for here in Tx.
 
The roaring fan clutch isn't necessarily a bad thing. I love to hear mine roar to life in the morning, but then you should hear it mellow out after 15-30 seconds upon a cold start. When wheeling in 4 low and CDL engaged it definitely roars.

Is there a chance for some reason it isn't going into OD like you explained? Just listen to your gears from a stop. Should hear/feel it go into second, third, OD, torque converter lock up.

At 60 MPH I am right around 2k RPMS, what are you at? ( stock tire size ) 65 mph is around 2200, 70 is around 2400.

>> Oh wait, are you in a 5 speed? what year is your rig?
 
I get a pathetic 12 mpg.
I get this with regular city driving. 8 mph when towing 2,600 lb travel trailer. Not unusual.

Also, sorry if this seems like a no-brainer suggestion, but make sure your "power" button isn't engaged. When engaged, this will cause the transmission to shift at a higher RPM. Additionally, make sure your "o/d off" switch isn't engaged.
 
I get this with regular city driving. 8 mph when towing 2,600 lb travel trailer. Not unusual.

Also, sorry if this seems like a no-brainer suggestion, but make sure your "power" button isn't engaged. When engaged, this will cause the transmission to shift at a higher RPM. Additionally, make sure your "o/d off" switch isn't engaged.
Also possibly the CDL is engaged and the light isn't working?? Seems like that light on the dash has been known to go out often.

You should be able to tell if the button is depressed or just do a tight circle and see if it bucks a little
 
It's been my experience that if it's in the 90's outside it will stay locked up most of the time. It roars big time in the morning when I first start it up. That's what it's supposed to do. After about thirty seconds it should beck off. But I notice when I'm driving if it's pretty hot you can here it roaring. Given that you're in Arizona I would assume it's fairly hot. The engine and trans will feel fairly different from your 4runner primarily due to the weight. A stock v8 4runner is no slouch when accelerating. A loaded 100 series is SLOW. I've owned over 40 vehicles and the only one that was slower than my 100 series were the two 80 series that I owned. 12mpg is about what I get out of my lx and it's completely stock. Considering yours looks fairly loaded I'd say the fact you're getting 12mpg is better than most. All in all, it sounds like you've described a normal loaded lx.
 
Have you checked if you have any codes? I don't believe your symptoms are normal at all, although checking that all the lights and switches are in working order, as others have said, is a good first step. If it is roaring from the getgo before the truck even has a chance to warm up (outside of the first few seconds, although that is not experienced by everyone), then I think you may have gotten a bad fan clutch. If it starts normal but locks up regularly and says that way, even on the highway, you have a cooling system issue (thermostat, radiator, etc) that you need to sort. You may want to get an OBD app (Fusion or others) so you can see what the actual coolant temp is.
 
Thanks to all for chiming in.

Year = 2007 so Five speed
No, CDL is not engaged
No, PWR button is not engaged
All the lights and switches are in working order
No codes - I use Techstream. Although I may download some ODBII phone app to scan via BT ELM327 as I drive to see the coolant temps - the only old windows 10 laptop I run the Techstream on has to be plugged in all the time with a near dead battery and I only use it in my garage plugged in while working on the vehicle

Fan clutch - yes AZ is hot, but none of the vehicles I've own sounded like a dump truck - it's definitely not normal. In the morning when I leave for work from a cold start, I don't think it roars as much, but it starts doing that after a few minutes. honestly I can't quite tell whether it does it on the freeway because all sounds just get drowned out on the freeway. But on surface streets it definitely always roars with the exception of the first few minutes after the cold start. The new one I put in is an OEM part from the dealer. I haven't scanned for coolant temps, but at least it's not showing overheating from the temps gauge on the dash.

The transmission - I don't have an OD button on this 2007. I believe it's the pre-2003 trucks that have that? it's not like it won't go into OD - it does go into it. When it does, the cruising rpm at 60, 70 mph etc. are like what you all said above. I'd say that it has delayed shifting? Bad solenoids? Sometimes takes a lot longer than I expect it to and I don't even gun it - I have a very light foot, a habit I've formed since I moved to the v8 4Runner 15 years ago :) Since I'm so light-footed, I didn't even notice anything abnormal about the transmission the first couple of months until the first time I drove up north with a lot of climbing. It would get to over 4000 - 4500 rpm and stay there even after I'd leveled out from climbing for a long while. It seemed the whole trip it struggled to shift into the next gears - no slipping or anything like that though. Since then, I've noticed the occasional delayed shifting locally on flats too. Sometimes it also seems to be stuck - resistance on the gas pedal and rpm hangs around 2000-2200 and won't go up, until I really try to depress the pedal. I have flushed the transmission fluid - didn't drop the pan, just drained the pan, filled, then drained and filled 2-3 quarts at a time from the return line exiting the Transmission Cooler while shifting through all the gears. Total of 14 quarts Toyota WS. Used Techstream to check temps to perform level check. I actually had to do it twice since the first time I did it was a 2-3 hours after I finished the flush - ambient temp was 108 at 8:00pm (probably higher in my garage) and the transmission temps were at above 115 already when I first started the truck! So I had to wait to do it again the next morning when it was cool enough for it to be in temp range. I'm not sure I've seen significant performance improvement from the fluid exchange.



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Thanks to all for chiming in.

Year = 2007 so Five speed
No, CDL is not engaged
No, PWR button is not engaged
All the lights and switches are in working order
No codes - I use Techstream. Although I may download some ODBII phone app to scan via BT ELM327 as I drive to see the coolant temps - the only old windows 10 laptop I run the Techstream on has to be plugged in all the time with a near dead battery and I only use it in my garage plugged in while working on the vehicle

Fan clutch - yes AZ is hot, but none of the vehicles I've own sounded like a dump truck - it's definitely not normal. In the morning when I leave for work from a cold start, I don't think it roars as much, but it starts doing that after a few minutes. honestly I can't quite tell whether it does it on the freeway because all sounds just get drowned out on the freeway. But on surface streets it definitely always roars with the exception of the first few minutes after the cold start. The new one I put in is an OEM part from the dealer. I haven't scanned for coolant temps, but at least it's not showing overheating from the temps gauge on the dash.

The transmission - I don't have an OD button on this 2007. I believe it's the pre-2003 trucks that have that? it's not like it won't go into OD - it does go into it. When it does, the cruising rpm at 60, 70 mph etc. are like what you all said above. I'd say that it has delayed shifting? Bad solenoids? Sometimes takes a lot longer than I expect it to and I don't even gun it - I have a very light foot, a habit I formed since I moved to the v8 4Runner 15 years ago :) Since I'm so light-footed, I didn't even notice anything abnormal about the transmission the first couple of months until the first time I drove up north with a lot of climbing. It would get to over 4000 - 4500 rpm and stay there even after I'd leveled out from climbing for a long while. It seemed the whole trip it struggled to shift into the next gears - no slipping or anything like that though. Since then, I've noticed the occasional delayed shifting locally on flats too. Sometimes it also seems to be stuck - resistance on the gas pedal and rpm hangs around 2000-2200 and won't go up, until I really try to depress the pedal. I have flushed the transmission fluid - didn't drop the pan, just drained the pan, filled, then drained and filled 2-3 quarts at a time from the return line exiting the Transmission Cooler while shifting through all the gears. Total of 14 quarts Toyota WS. Used Techstream to check temps to perform level check. I actually had to do it twice since the first time I did it was a 2-3 hours after I finished the flush - ambient temp was 108 at 8:00pm (probably higher in my garage) and the transmission temps were at above 115 already when I first started the truck! So I had to wait to do it again the next morning when it was cool enough for it to be in temp range. I'm not sure I've see significant performance improvement from the fluid exchange.



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nice job. and you even got the correct hose for transmission fluid change.
 
Does the truck "glide" alright when you're off the accelerator? Almost sounds like its trying to push through a lot of resistance (like dragging brakes), which would also potentially cause it to run hot. Are those tires 35s? If so, was it regeared?
 
It coasts fine, no dragging brakes. The tires are 34s, no need to regear. The roar was present with factory rims and tires on.
 
Sounds like you've covered a lot of potential causes. The only other problem that comes to mind is airflow restriction. Are your radiator or condenser fins plugged with dirt/dust/debris? Also check in between the radiator and condenser.
 
My 2006 lc has always been loud on startup and and I too replaced the fan clutch which didn’t make any difference.

I forget how many rpms it revs to on cold startup but it quiets down after a couple three minutes.

I have a coworker with a 2007 lexus 100 and his doesnt roar like my 2006 - both vvti but there is obviously a noise diff on cold start.
 
List the part number of the FC you installed. Make sure the right one for the right application.

Start Engine from cold, idle for a couple minutes to shear the fluid back into the reservoir and shut off. Go and rotate the fan by hand- you shouldn’t feel too much resistance on a cool engine after only a couple minutes of operation.

The factory fill of silicon fluid in the Blue FC is usually under filled from AISIN maybe 20-25ml total thus causing it to spin more freely vs staying hooked up( fwiw-optimal volume is around 45-50ml). It is entirely possible the fluid is either greater than normal fill or the opening temperature of the internal valve is set wrong. Too much fluid will keep it engaged longer or fully when hot.

If you purchased from Amazon- return it and try another or if not returnable, open it up and reset the temp at which the valve opens and closes.
 
I see you monitor ECT on your phone app. But I did not see what ECT is and at what OATs and condition. i.e sunny, hot morning or 3PM sun cook and egg on the black top, RPMs, MPH, AC on, fuel trims, etc.?

I run logs both with Blue driver and I just got a OBDIImx+. Fuel trims, ECT and with OBDII ATF 1 & ATF 2 are my staples I log. BTW ATF level is set watching ATF #1, in the 06-07. Earlier years we just get ATF temp 1.

I've had issues with getting ATF temp low enough to set level also, in only a few 06-07. I like to set level with ATF #1 temp at 97-100F, than check again at 115F (not letting drain out at the 115F, so I know level at max). BTW, I like your return line set up to fill.

Some AT, fluid temp jump up to fast during flushing:
What I've notice is 2 issues causing high ATF temp during fill.
1) Fins of radiator(s) clogged, re-sticking air flow.
2) A weak transmission. By this I mean they seems to have been run for to many miles to low (factory fill) before topped to TSB (97-115F) level, which is higher than factory fill. These transmission are usually ones, run a bit harder while low. i.e tow, slow grinding hot passes off road, towing. In them, even after a full 12 qt flush ( I almost always do the full 12 qt flush) they run hotter. I like to see normal op temp of transmission in the 155 to 165F, while driving. But for me I only see OATs of 100F on sunny days.

For what it's worth. I've just started using a new Mobil ATF MV full synthetic, this year. Mobil (unfortunately not Mobil 1) just this last year reformulated and approved for Toyota III, Toy IV and WS.

Also note; we've 2 fans running on cold start up, in the VVT engines. The S.A.I pump (blower fan) and engine cooling fan. (S.A.I should shut down after about 90 seconds).


Mod for S.A.I
 
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Update: my 2006 lc idles to 1,400 rpms on cold start with a/c on.

My radiator is only a few months old.
 
My 2006 lc has always been loud on startup and and I too replaced the fan clutch which didn’t make any difference.

I forget how many rpms it revs to on cold startup but it quiets down after a couple three minutes.

I have a coworker with a 2007 lexus 100 and his doesnt roar like my 2006 - both vvti but there is obviously a noise diff on cold start.
The cold start is normal. About 1400 rpm with fan coming on loud as it should. Fan speed reduces after 30 seconds or so. Idling a minute or two, rpm drops to 800 in Park. I get the abnormal roar after I drive it for a few minutes.
 
List the part number of the FC you installed. Make sure the right one for the right application.

Start Engine from cold, idle for a couple minutes to shear the fluid back into the reservoir and shut off. Go and rotate the fan by hand- you shouldn’t feel too much resistance on a cool engine after only a couple minutes of operation.

The factory fill of silicon fluid in the Blue FC is usually under filled from AISIN maybe 20-25ml total thus causing it to spin more freely vs staying hooked up( fwiw-optimal volume is around 45-50ml). It is entirely possible the fluid is either greater than normal fill or the opening temperature of the internal valve is set wrong. Too much fluid will keep it engaged longer or fully when hot.

If you purchased from Amazon- return it and try another or if not returnable, open it up and reset the temp at which the valve opens and closes.

Fan clutch is OEM from the dealer.

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Before cold start, spinning the fan with my hand gets it to spin 1.5-2 blades. Cold start then idle a couple of minutes then shut off. Spin it with my hand again, about the same maybe just a tad looser about 2 blades turn.
 

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