[1988_4wd]

I have an '88 pickup with 180k miles. A whine has developed in the engine, only after I've driven a couple miles, and it gets louder the farther I drive. It gets louder at higher revs. I popped the hood and the sound is coming from the alternator area. Has anyone had the alternator bearings go out in a similiar manner? Any thoughts on diagnostics before I spend $100 and a couple hours to replace the alternator? Any thoughts appreciated.

If it is the bearings, I expect they will seize at some point, shredding the belt.

 

[crbenton]

I can't remember....... Is the alternator in the loop with other pulleys? If not take the belt of for a few min. Just a thought.

 

[Pink Taco]

I can't remember....... Is the alternator in the loop with other pulleys? If not take the belt of for a few min. Just a thought.

yeah you should be able to just take off one belt at a time to pinpoint the source of the noise. It could also be a tensioner pulley and not the alternator.

 

[85buggy]

Could be another pulley but Im laying my bet on the alternator just because thats what mine is doing right now and its the same thing it did the last time just before it died. If you can have it rebuilt or do it yourself because last time I checked with my local carquest the alternator was around 200 bucks.

 

[tbplus10]

Either get ahold of a mechanics stethescope, or make one with section of metal tube and some rubber tubing.
This helps to pinpoint engine sounds.

Tim

 

[Janster]

I have an '88 pickup with 180k miles. A whine has developed in the engine, only after I've driven a couple miles, and it gets louder the farther I drive. It gets louder at higher revs. I popped the hood and the sound is coming from the alternator area. Has anyone had the alternator bearings go out in a similiar manner? Any thoughts on diagnostics before I spend $100 and a couple hours to replace the alternator? Any thoughts appreciated.

If it is the bearings, I expect they will seize at some point, shredding the belt.

I don't know about the 88's.... but in my 96 Taco, I had a similar problem.

I removed the alternator and one of the bearings was indeed 'worn' (rough spots). I took it to a local *Starter & Alternator* shop and they pressed new bearings in and they sandblasted the inside (full of mud). It only cost me like $40.

 

[85sfarunner]

Don't know if you have the 3.0 or 22RE in your truck?

For the 22RE you can get the bearing for $6.00 from the dealer,

part# 90099-10091

It will work in the alternator or the pulley.

I think you can get the same size bearing from NAPA with this standard part #,

6203-RS

It's a little cheaper.

 

[1988_4wd]

Thanks for all the suggestions.

The whine seems to be intermitent, so I have not been able to diagnose yet. It only happpens after about 15 minutes of driving. The last time it started at 15 minutes, but stopped 5 minutes later. It has been warmer lately here- maybe that influnences it? I will let everyone know what I figure out. I have the 6cylinder engine.

 

[98 Taco]

is it the original alternator? Damn! mine was toast after my first muddn' trip in Indiana.
You can jus about replace the alt with an aftermarket unit for $150 and have a new warranty.
good luck!
consider replacing the belt as well