4th Gen whine at 70-75

[ArthurKotb]

My 2004 V8 has had a whine at 70-75 for years but it seems to be getting worse, particularly when I'm towing my boat or travel trailer. The sound seems to be coming from the front passenger side but you know how it is with sounds in a car.

When I'm at 70-ish (where I travel most of the time) I hear the whine and if I let up on the gas it's completely gone. If I accelerate it gets a little louder and if I let up a little on the gas it gets quieter. There is no issue with power or shifting. There's no other noise with it. It's just an annoying whine.

I had an '89 V6 Toyota pickup and it was the differential but the noise never got any louder but was present at 70-75. I suspect the rear differential or perhaps the driveshaft. This is my first FT4WD so I don't know if that has anything to do with it.

Is this just something that's common, like my '89 pickup?

 

[rdruss]

You might check your wheel bearings. Jack up the front and do the grab wheel at 6 & 12 and try and rock wheel to and fro, if it rocks, wheel bearing probably bad.

 

[ArthurKotb]

Thanks for the reply. I've heard wheel bearing noise on other cars I've owned and it doesn't sound like this noise; more like differential. I will add it to my list of items to check the next time I take it into the shop for maintenance.

I don't hear the noise at any other time except at the highway speed I usually travel at; 70-75. It's been making the noise for about 40-50K miles and other than hearing it, no indication of any problems.

 

[maxdef]

I've had what sounds similar to yours- a whine around 55-65 that is matched to pressing the gas. I hear it often of course, and I've been suspicious it's somewhat related to the exhaust, perhaps at the y-pipe to catback junction. I ordered a new donut gasket but the old one appears pretty fused into place so I haven't been able to swap it out to test my theory.

 

[ArthurKotb]

I've also considered the exhaust manifold as being a possibility. My oldest son has a 2006 T4R V8 SE very similar to mine. He started hearing a noise on startup but nothing afterward, once the engine warmed up. Since the noise seems to be coming from under the passenger side could be the Y pipe. I'll add that to the maintenance list. I'm almost at the 160K mark and that's about where he first noticed his noise. He's not had it fixed and sold it to another family member, so it lives on.

Thanks for the suggestion.

 

[Moist]

My 2004 V8 has had a whine at 70-75 for years but it seems to be getting worse, particularly when I'm towing my boat or travel trailer. The sound seems to be coming from the front passenger side but you know how it is with sounds in a car.

When I'm at 70-ish (where I travel most of the time) I hear the whine and if I let up on the gas it's completely gone. If I accelerate it gets a little louder and if I let up a little on the gas it gets quieter. There is no issue with power or shifting. There's no other noise with it. It's just an annoying whine.

I had an '89 V6 Toyota pickup and it was the differential but the noise never got any louder but was present at 70-75. I suspect the rear differential or perhaps the driveshaft. This is my first FT4WD so I don't know if that has anything to do with it.

Is this just something that's common, like my '89 pickup?

How's your transfer case? Mine has a whine at low speeds from 0-30. When mine was low on fluid I was getting a horrible whine through gears 1-2 and through all low range gears.
Otherwise yeah I'd check the diffs. Weird that its 70-75 though. I'm too afraid to mess with the FT4WD's LSD's.

 

[ArthurKotb]

How's your transfer case? Mine has a whine at low speeds from 0-30. When mine was low on fluid I was getting a horrible whine through gears 1-2 and through all low range gears.
Otherwise yeah I'd check the diffs. Weird that its 70-75 though. I'm too afraid to mess with the FT4WD's LSD's.

Thanks for the reply, Moist.
I had all of the fluids changed by my trusted, Toyota certified shop in Dec 2024; transfer, tranny and diffs; no oil spots on the ground. I don't have any noise at all during shifting. It's only on the highway at the 70-75 range, worse when towing my boat or Airstream travel trailer and adjustable by lifting up on the gas or pressing down. At every oil change I lube the U-joints and shafts.

Other than the annoying noise, there is no difference in performance.

 

[ArthurKotb]

How's your transfer case? Mine has a whine at low speeds from 0-30. When mine was low on fluid I was getting a horrible whine through gears 1-2 and through all low range gears.
Otherwise yeah I'd check the diffs. Weird that its 70-75 though. I'm too afraid to mess with the FT4WD's LSD's.

Thanks for the reply, Moist.
I had all of the fluids changed by my trusted, Toyota certified shop in Dec 2024; transfer, tranny and diffs; no oil spots on the ground. I don't have any noise at all during shifting. It's only on the highway at the 70-75 range, worse when towing my boat or Airstream travel trailer and adjustable by lifting up on the gas or pressing down. At every oil change I lube the U-joints and shafts.

Other than the annoying noise, there is no difference in performance.

 

[Moist]

Thanks for the reply, Moist.
I had all of the fluids changed by my trusted, Toyota certified shop in Dec 2024; transfer, tranny and diffs; no oil spots on the ground. I don't have any noise at all during shifting. It's only on the highway at the 70-75 range, worse when towing my boat or Airstream travel trailer and adjustable by lifting up on the gas or pressing down. At every oil change I lube the U-joints and shafts.

Other than the annoying noise, there is no difference in performance.

That's good there isn't any performance difference. Figured it'd worth covering all bases :biggrin1:
My next guess would be some sort of an engine sound. Maybe try holding the RPM at whatever your tach reads when you tow. Maybe it's something in the accessory drive.
My only other thought might be something up with 5th gear. I know nothing about transmissions though so I'm no help.

 

[MrSeth]

Are you still on OEM fuel injectors?

 

[ArthurKotb]

That's good there isn't any performance difference. Figured it'd worth covering all bases :biggrin1:
My next guess would be some sort of an engine sound. Maybe try holding the RPM at whatever your tach reads when you tow. Maybe it's something in the accessory drive.
My only other thought might be something up with 5th gear. I know nothing about transmissions though so I'm no help.

The owner's manual says to tow in 4th, but I've always pulled with 5th on level ground. If I see the RPMs starting to drop I downshift. That may have been what has caused the problem but other than the whine I don't notice anything different. I pulled the travel trailer a couple hundred miles up and back this past week and didn't notice the sound at all, but it was rain, headwind and heavy traffic most of the trip so probably focused more on the driving.

The tach reading varies, depending on the gear I'm in, but the whine remains the same, dependent on the speed of the car and not RPMs

 

[ArthurKotb]

Are you still on OEM fuel injectors?

Yes, no change there. I'm on the 2nd set of plugs and I've already bought new ones so I can change out this spring. Engine performance is not affected by the whine.