Squeeling noise while on road trip, advice needed

I'm on a road trip right now and I've noticed a squealing noise when I decelerate and let off the gas when I'm going at slow speeds in first gear or while I'm accelerating in reverse. I'm not sure if this has something to do with the belts or the driveshaft. When I rev the truck in neutral, there is no noise. It's only when I let my foot off the gas when I'm in first gear or reverse, when my foot is on the pedal and I'm accelerating in reverse. I did have the all belts (serpentine, etc... i think) replaced around 50,000 kilometers ago when I did my timing belt and water pump. Also, I may have noticed some noise when I'm turning out full crank in low speed.

It is a 1998 3.4 liter v6 4x4 manual. I don't know if this model drive shaft has a carrier bearing or not.

I'm hoping I can just make it home and deal with this when I get home. What do you think I should do? Around a 10 hour drive away from home.

 

Sounds vacuum leakish to me. Get a can of carb cleaner and while the motor is running spray it at the upper manifold to lower manifold area and see if the idle changes. Then mist it around the lower intake to heads, then injector area... this what i am thinking, when you decelerate, especially with a manual transmission, the weight of the truck drives the motor and the motor will develope higher than normal vacuum and a partially sucked in gasket will whistle like a blade of grass between your thumbs. Factory toyota upper to lower manifold gaskets are 3 layer steel for this reason.

The second test is check the brake vacuum booster. Turn the motor off and press the brake pedal, let it up, then press it again, you should get 1 and 1/2 pedal pumps before the pedal gets hard, if it gets hard immideatly, your booster is leaking, that could be the whistle too.

Very tough to diagnose a noise over the internet.

 

Nah you just need to hold the computer closer to the Taco!

Can you determine where it's coming from, front, back, under hood? Though you did the belts 50K ago, it's entirely possible it's belt squeak noise which shouldn't leave you stranded. Most of the time you only hear it on startup, but I've heard it under other conditions. It's possible the alt belt is loosening/stretching.

 

no the truck is idling perfectly fine so I don’t think it has anything to do with the vacuum

 

i’m thinking maybe one of the belts but I don’t know. It only happens when I’m going under 25 km an hour and when I’m accelerating so I don’t know that I’m kind of ruling out the belt because of that and also I’m noticing a squeaky noise when I turn as well so I think maybe it might have something to do with my steering. I don’t know

 

I would guess that is a different issue. You've checked the fluid level on the PS, right? Again this won't leave you stranded (unless the system runs dry but it will make LOT of noise before that happens) but a lot of times the screen in the reservoir gets clogged, remove it, clean the reservoir, flush the system with fresh ATF and that should go away. If not the pump is probably on its way out.

 

Thanks, I'll check the fluid level. I did have the power steering pump replaced around 70,000 kilometers ago, so I don't think it's the power steering pump. It almost sounds like it could be coming from the CVs or something but replaced those like five months ago, so yeah, I'm not really sure.

 

This is pretty much the exact sound I am having... I think its probably the ujoints need to be greased or the carrier bearing? but i read on here that some models don't have carrier bearings?

https://www.youtube.com/watch?v=Oa6aaI8x7ZI&ab_channel=JacobStewart

 

OK, bit of an update when I’m going in reverse at slow speed, I can hear the squeeling sound but then when I press my clutch in the sound goes away so I don’t know what I would have to do with my clutch being engaged or not thought that might be relevant? i still think it’s driveshaft related, but haven’t gotten around to greasing the shaft. but what would the clutch have to do with the driveshaft? if the clutch is engaged the driveshaft is still spinning so i don’t get it?

 

Throw out bearing may be suspect.

 

interesting. you may be right. that sounds expensive. how long do you think i could go before replacing it?

 

As long as you can tolerate that annoying noise

in college (poor/no money)
My car doing the same
I discovered I could get squeak sound to go away if I pressed c pedal just barely
I adjusted clutch pedal throw
Sound went away
Of course, this is band aid solution