Hum Noise identification..........

[landonridge]

My 1995 LC has developed a humming noise this seems to be coming from the front area of the cruiser. I can hear it at lower speeds but it is more noticeable around 50-60mph. It does go away when I let off of the accelerator and when I go over a hump in the road. Going uphill makes the noise louder (when there is more toque required). There isn't a vibration that is noticeable. Any idea what it may be or how I can go about identifying the issue?

 

[inkpot]

Grease the joints yet?

 

[amgraham]

Obviously, check the easy stuff (u joints, wheel bearings, etc.). Is it kind of a whine noise? If it is it's more than likely in the diff. Mine does it bad and I've had the front diff out 3 times trying to fix it but the pattern still sucks on the ring and pinion. I think it's just worn in on mine to the point where it needs a new gear set. I picked up a low mileage used diff that I'm going to swap in as soon as I have the time. Till then I'm running without the front driveshaft and the center diff locked just to keep my sanity.

If yours is minor some Lucas Stabilizer in the front diff may help. It quieted mine down a bit.

 

[LXMUTT]

I'm currently working on a 80 with this exact thing. On this 80 the hum is high pitch and is almost a whistle when the gas pedal is applied. I am having a hard time pin pointing it because when I turn my head to listen for it, the sound changes. The exhaust tip was broken off and was replaced without the resonator so I'm hoping its just whistle from that as others here in the forum have mentioned. Ill be watching this to see what people com up with