Gen 3 grinding noise

[1morebike]

Hi all

I have been having a problem that is driving me crazy. When driving down the road usally when I'm coasting or just light on the gas I get a grinding noise. The noise will get louder the faster I go and if I come to stop it will grind real slow then a big clunk and all is fine. I found I can also make it go away if I shift in 4hi. If I put the truck in netural it still makes noise. I took to my mechanic but it so spuratic that he hasn't heard it yet. The truck is 2003 150,000 miles. All fluids were done in the last year using mitsu oil. Any ideas would be awesome right now I don't really want to drive much.

 

[vk_miniatures]

Check your driveshafts u-joints

Sent from my SM-G965U using Tapatalk

 

[1morebike]

That's what thought my mechanic checked them today and said they are fine. Really only has one u joint the rest are cvc irc

 

[offthepath]

It's not the u joints. Mine does the same thing. Only about 2-3 times a year. There was another post on the same topic about a month ago. I'm pretty sure he found a solution related to the front axle or Transfer case 4x4 system. Do a search. I think it was title Gen 3 grinding too.....

 

[1morebike]

Sweeeeeet thanks I'll do some searching. Mine does almost every time I drive it.

 

[plh]

Lubing the differential engagement shaft comes to mind, it is supposed to cycle when in 2WD with every startup. Normally when the vacuum is off, the shaft engages, then when the vehicle is running (2WD) and pulling a vacuum, the shaft disengages. Maybe yours is sticky.

 

[Skidmarkart]

What plh said above.

Default for the Gen 3 is 4wd, when the vacuum "switch" that puts it in 2wd starts to fail, you get that issue. You can get the generic part that usually fails from Amazon pretty cheap (like $25 IIRC). I hear the OEM part lasts longer though (I think it is around $120). Leave it in 4wd until you get it fixed to prevent damage ( I am in the middle of this same repair myself, I have the parts but have not done the work yet). Post back if you do the job, I will do the same if I beat you to it.

Good luck.

 

[eyehate]

I am in the same boat, just ordered 2 of these https://www.amazon.com/gp/product/B00SO44A96/ I'll post up in my thread when i get them on weds to see if it solved the issue.

*edit upon clicking my link I apparently ordered the last 2 lol.