Weird Hum Coming From The Front End

Joined
Aug 3, 2014
Messages
411
Location
Monument
I don't really understand what is going on. Driving home tonight I noticed a weird faint hum coming from the front end which I believe to be is the axle. I have heard the front axle make noises before but its only when it is bellow zero just pulling out of my driveway for 30 seconds then it goes away.

I have no reason to believe it is the Engine as it is running cool and pulls strong and seems happy. This very faint hum noise only occurs above 70 mph. 65 mph it sounds fine. I did think at first it was a driveline vibration but I have had my 3-inch lift on for 6 months with no issues and no castor correction.

I don't understand where the best place to begin diagnosing the issue. When I purchased the cruiser a year and a half ago I took it to my buddys shop and the diff fluid looked clean and full and that was only 10k ago. I will verify that is the case tomorrow but my cruiser doesn't leak anything so I doubt that is the issue. The birfields I check once a month and they are full of grease. The wheel bearings have a slight amount of play in them. Could that be it? I am open to any suggestions on what it could be and where to begin diagnosing.

One other question I have is can I still drive it? Its my only vehicle and I kind of need to drive it daily.

Thank you!
 
Joined
Aug 3, 2014
Messages
411
Location
Monument
Check your u-joints and wheel bearings first. Also the level of oil in your diff.

Will do. I have been watching videos on failing wheel bearings and u-joints. It does not sound like a wheel bearing at all. It is possible it could be a u-joint. Still does not sound nearly as bad as any video I have found. It is really hard to hear... I have to turn off my radio and listen really closely to hear it. So maybe i am just catching it early?
 

inkpot

SILVER Star
 
 
Joined
Jan 30, 2003
Messages
13,290
Location
All over Arizona
Check your u-joints and wheel bearings first. Also the level of oil in your diff.
Grease one u joint at a time then test drive. That way you can identify the culprit. If you have not greased them for a while, then it may just be looking for a little attention. With a dose of grease it may be fine it you cannot feel any play in that joint. John
 
Joined
Aug 3, 2014
Messages
411
Location
Monument
Grease one u joint at a time then test drive. That way you can identify the culprit. If you have not greased them for a while, then it may just be looking for a little attention. With a dose of grease it may be fine it you cannot feel any play in that joint. John

Will do. I try to stay up on greasing them however it due to weather it has probabaly been 2 months and I have been driving it non stop.

I will do that first thing tomorrow and report back.

Thanks!
 

Dave 2000

Not all Land Rovers are useless!
 
Joined
Jan 24, 2009
Messages
3,733
Location
Spain
Swap tyres front to rear and try that, could be some odd wear pattern developing? If nothing else they can be discounted and takes ten minutes.

regards

Dave
 

bajaphile

Boojum Hugger
SILVER Star
 
Joined
Apr 6, 2008
Messages
1,990
Location
Solana Beach, CA
The wheel bearings have a slight amount of play in them. Could that be it?
Your wheel bearings shouldn't have any play at all. If you feel that the noise might be coming from the wheel areas, you can open up the hubs and and check your axle nuts are correctly torqued. What do the knuckles look like? Have they been rebuilt? I would lube u-joints before going in there. Also use a flashlight and inspect your radius arm bushings, panhard bushings, etc.
 
Joined
Aug 3, 2014
Messages
411
Location
Monument
Your wheel bearings shouldn't have any play at all. If you feel that the noise might be coming from the wheel areas, you can open up the hubs and and check your axle nuts are correctly torqued. What do the knuckles look like? Have they been rebuilt? I would lube u-joints before going in there. Also use a flashlight and inspect your radius arm bushings, panhard bushings, etc.

Good to know. I will put it up on jack-stands today and see if I find any play. The knuckles have not been rebuilt to my knowledge however they have plenty of grease and are not puking the grease out. There is also no clicking going around corners.
 
Joined
Jul 20, 2004
Messages
24,051
Location
Chandler, AZ
... The knuckles have not been rebuilt to my knowledge however they have plenty of grease and are not puking the grease out. ...
I would check them, overtime the grease is lost. If low, the bushing grease starved, they can make a hum/grumble at highway speeds. It's easy, clean then remove the inspection plug, with a small screwdriver remove the skin of grease from the hole, look into the hole. If you can see the bushing, add some moly grease.
 
Joined
Nov 9, 2012
Messages
6,658
Location
Olathe, KS, USA
Maybe it's humming because it forgot the words........



Wheel bearings. You already know they are "loose." Fix those then see if it learns the words or not.

I had one front WB loose and it made no noise, but my steering started getting loose and it was grabbing every seam on the road. I pulled it apart and repacked the WB, problem solved. Mine got loose because I forgot to clean the front differential breather when I rebuilt is and it forced the gear oil to the birfs causing Birf soup and that ended up diluting the grease in the wheel bearings. Cleaned and repacked and problem solved.

The bearings will hum because they are misaligned.
 
Joined
Aug 3, 2014
Messages
411
Location
Monument
Maybe it's humming because it forgot the words........



Wheel bearings. You already know they are "loose." Fix those then see if it learns the words or not.

I had one front WB loose and it made no noise, but my steering started getting loose and it was grabbing every seam on the road. I pulled it apart and repacked the WB, problem solved. Mine got loose because I forgot to clean the front differential breather when I rebuilt is and it forced the gear oil to the birfs causing Birf soup and that ended up diluting the grease in the wheel bearings. Cleaned and repacked and problem solved.

The bearings will hum because they are misaligned.


Think you might be right....I jacked the front end up today and shock the wheels and there is some noticeable play. Filled the birfields to the top full of grease (they were't that low) and the u-joints look dry but I cant get my stupid grease gun to pump grease into the zirks for some reason. So I will continue to work on that however I am 99% sure it is the wheel bearings. So I need some input though. I am currently in high school and don't have a lot of time to work on the cruiser right now. For me to repack the wheel bearings (with my dad who knows how but is a pilot and is gone 3/4 of the time) it may take me a month or two to find the time. So I can either weight till I find the time or I just got an estimate from brakes plus and they say they can do it for $250. I only trust them because there is a Toyota guy there that has an 85 4runner with all sorts of upgrades and knows the land cruiser pretty well. Is $250 a good price? What is the best way to go about doing this.
 
Joined
Dec 9, 2016
Messages
94
Location
Tyler TX
Dude if you don't have time to work on it now, you definitely won't when you have a career, kids, and taxes to pay.

You can make the time. Don't be intimidated. Grab a few bottles of water and fire up the Youtube.

It is literally a 45 minute job. Maybe 1.5 hours your first time.
 
Joined
Aug 3, 2014
Messages
411
Location
Monument
Dude if you don't have time to work on it now, you definitely won't when you have a career, kids, and taxes to pay.

You can make the time. Don't be intimidated. Grab a few bottles of water and fire up the Youtube.

It is literally a 45 minute job. Maybe 1.5 hours your first time.
Appreciate the feedback. Don't get me wrong I would totally rather do this myself I'm just consernied if I don't get it done soo I will harm it.
 
Joined
Aug 3, 2014
Messages
411
Location
Monument
Dude if you don't have time to work on it now, you definitely won't when you have a career, kids, and taxes to pay.

You can make the time. Don't be intimidated. Grab a few bottles of water and fire up the Youtube.

It is literally a 45 minute job. Maybe 1.5 hours your first time.

Well you convinced me. I am going to attempt to do this tomorrow afternoon. Tonight will consist of a lot of youtube videos and laying out all the tools needed.

Thanks!
 
Joined
Dec 9, 2016
Messages
94
Location
Tyler TX
You can do it!

There are lots of great threads here too.

Once you have it torn down inspect the bearing races to make sure they weren't beat up too bad. You want a blemish free dull finish.

The most critical part is getting the inner nut torqued properly. Do it a few times on the first one to get comfortable and find the "feel" for it.

You'll want the rotor to turn freely, but not loose enough to have play if you hold the rotor at 12:00/6:00 and rock it up and down.

It's a "snug" thing.
 
Joined
Aug 3, 2014
Messages
411
Location
Monument
You can do it!

There are lots of great threads here too.

Once you have it torn down inspect the bearing races to make sure they weren't beat up too bad. You want a blemish free dull finish.

The most critical part is getting the inner nut torqued properly. Do it a few times on the first one to get comfortable and find the "feel" for it.

You'll want the rotor to turn freely, but not loose enough to have play if you hold the rotor at 12:00/6:00 and rock it up and down.

It's a "snug" thing.

Good to know. Thank you! I will report back on how it goes tomorrow. Thanks!
 
Joined
Nov 9, 2012
Messages
6,658
Location
Olathe, KS, USA
Find the procedure from @Tools R Us on here with a search. It's worth the time.

Good luck!

I recommend Lucas RedNTacky #2 grease for the wheel bearings.

O'Reilly also carries a sealant that is a black rubber base for sealing the drive flanges back on. Also rent a torque wrench from them fir adjusting the WB. also need the bug socket for the nuts. O'Reilly may have that as well. Also need brake cleaner to clean the stuff and maybe a bit if parts washer fluid or gasoline (not recommend due to safety).
 
Joined
Aug 3, 2014
Messages
411
Location
Monument
Find the procedure from @Tools R Us on here with a search. It's worth the time.

Good luck!

I recommend Lucas RedNTacky #2 grease for the wheel bearings.

O'Reilly also carries a sealant that is a black rubber base for sealing the drive flanges back on. Also rent a torque wrench from them fir adjusting the WB. also need the bug socket for the nuts. O'Reilly may have that as well. Also need brake cleaner to clean the stuff and maybe a bit if parts washer fluid or gasoline (not recommend due to safety).


Thanks for the help! Had success today! I followed a YouTube video I found on an old 4Runner with Solid Axle and followed it from the there. It took me a while and a couple of times I just had to get up and walk away from it for a while but it was overall pretty straight forward just really messy. I ended up using the red and tacky grease. Went through a lot of brake cleaner trying to clean everything and used the sealant you recommend. Thank you for all the help! And for anyone intemidaed about doing this don't be! It's not that hard of a job just time consuming and messy. It took me a total of 2 and a half hours.
 
Top Bottom