Front end squeaks only in 4wd

Been reading this forum for a while, lots of great info here, but noticed something today that I couldn't find on here. I was driving on the back part of the property to collect a bunch of dead brush and branches, threw it in 4lo because the 4wd doesn't get used much here in the summer, and noticed a squeaking coming from the front end when turning with it in 4lo or 4hi. Goes away as soon as I go back to 2wd. If I go straight, nothing, but as soon as I turn the wheels it's there. CV boots are dry and intact, in fact the only thing I've ever noticed with the skid plate off is the passenger side valve cover gasket leaking a little.

Any thoughts or suggestions for stuff to check? Thanks

And here's a photo of the truck, hate the running boards, but have an elderly parent that can't get in without them. They'll come off eventually.

 

Ever check the level or change the front diff gear oil? Fluid should be right up to the fill hole I believe. I’d at least start there.

 

What are the condition of the 21 year old bushings? I.E. shock mount, sway bar, steering rack, control arm. See, when it's in 4HI/LO and you turn on dry, relatively sticky surfaces, it puts those bushings in a bind. If they're old and worn, they're going to make noise. I had a similar problem with my '03 and that's what it turned out to be.

 

Thanks, haven't checked the bushings or the diff fluid yet. I have used the 4wd in the past without ever noticing this, and it definitely sounded more like a bushing squeak than any type of gear noise. The shocks have all been replaced at some point with KYBs, tires are slightly bigger than stock, and I'm not 100% sure it doesn't have a slight lift on it. Next time I feel like crawling under it I'll check that stuff, all I checked today after noticing the sound was the CV boots and they were nice and dry.

 

Another possibility when I check out 4x4 vehicles on other forums with a similar issue is the front driveshaft u-joints going bad.

 

That's the thing, I only hear it when in 4hi or 4lo with the wheels turned at low speed. I can drive up and down our dirt road in 4hi in a straight line and it's totally quiet. Also when turning at higher speeds in 4hi I don't hear it either. I'll try driving around some more tomorrow in 4hi and see if I can notice when it does and doesn't squeak.

 

Think about it from a logical standpoint.

It's only happening if 4WD is engaged. What parts are spinning, that would squeak, in that condition?

• CV Axles
• Front driveshaft
• If there are any bearings/bushings between the CV axles and gearbox or gearbox and driveshaft, those would be culprits as well

What would I do?

I'd inspect my CV axle boots for tears, and look for evidence of grease sling.

I'd use the center front crossmember to jack up both front wheels. I'd spin the wheels to get the CV Axles spinning, and see if I'm hearing a similar squeak. I'm an anal retentive motherfucker, so I'd probably throw another jack under each LCA to put my suspension under tension at ride height and test then as well, in case driveline angles play a role.

I'd also spin the front driveshaft to see if I hear it, with the truck on the ground.

However, let's break that down a bit more. What's required to get to this sound?

• 4WD engaged in any mode
• Turning the wheels

What is most engaged when turning the wheels while in 4WD? Your CV Axles. What makes groaning/squeaking/creaking when under-lubricated? Metal on metal contact.

Call this my wild prediction, but I suspect your CV axles are dry. Fortunatley OEM CV are said to be bulletproof. You can probably verify, get a packet of suitable grease, and shoot into the boot, or pop off the larger clamps and squeeze grease in.

 

Thanks, I'll throw it up on stands next week and check the front end components. Boots were the first thing I checked today and they were dry and intact. If I have time before then I'll try loosening up the CV boots and sliding them back to see what condition the CV axles are in.

The squeaking wasn't bad, it was just a new noise I hadn't heard before. Also are there any grease fittings I should be aware off on the suspension components that I should hit while I'm under the truck? Truck has about 250K miles and I've only had it for less than a year.

 

Oh hell yes.

You should be greasing the entire driveline front to back every 3k-5k with NLGI 2 moly grease. Sorry, that should've been obvious, and why I mention spinning the front driveshaft. When was the last time you greased the driveline? Not greasing can lead to running u-joints dry (squeak/vibration is symptom), and can also lend to an annoying 'clunk' when accelerating from a stop. The only reason I'm eyeballing the CV is because you mentioned turning being requisite, and your CV axle is most engaged when turning.

 

Ah, good to know. I found a diagram with the drive shaft grease fittings, any others I should be aware of or a good diagram of all of them before I dig through the FSM?

 

I mean, the FSM is king but read this: https://www.tundras.com/threads/black-hole-zerk-wtf.93630/

Obviously the FSM page on the 1st post is helpful but pay close attn to @FirstGenVol in reply #4. That's a hidden gem of info.

As for grease, these days I'm using Valvoline Palladium #2. NAPA carries it, often (strangely?) cheaper than most others. It's got everything you'll need for most everything on your chassis, and I stumbled into it because it's compatible with my aftermarket upper control arms. I prefer being able to load one tube of grease in one of my two guns and use it for almost everything, and that fits the bill.

 

Wow, $4.50 for that grease, I'll be picking some up tomorrow and crawl under the truck this weekend and hit everything. Can I use the same grease inside the CV boots or should I get something else? And thanks for the pointer on the sliding shaft zerk. Once everything is lubed I'll throw it in 4hi and see if it still makes any noise.

 

That's a tough question. I've never gotten a straight answer and I've heard the opinion of many hands. I was trying to figure this out recently because I am periodically slinging CV grease after lifting, which is typical.

I've read to use NKG 302 for inner and NKG 509 for outer
I've read to use 10077610 for inner, 10222673 for outer
I've read to use 90999-94161 for inner and 90999-94214 for outer
I've read you can use grease GKY H-15 for both
I know CRC makes CV axle grease, and I love CRC

I think at the end of the day, the big takeaway is, any of the above are probably adequate, but I'm not sure if u-joint and balljoint grease will do the job, so I'd stick with one or any of the above, or anything labeled "CV Axle Grease" to do the job.

 

I bought the Valvoline grease on @shifty` recommendation and have used it all over my truck, including the inner tie rod ends without issue. I base this on no expertise whatsoever other than “eff it, the last guy who owned this truck probably didn’t grease a damn thing so there’s no way using this on everything is worse than that”

 

I went to Napa earlier today and bought the last two tubes they had. Waiting for it to cool off a bit then I'll get to greasing everything.

I also spent some time last night checking the FSM and it doesn't say anything about different greases for inner and outer CV boots. Just has capacity and color = black.

Gonna hit all the zerk fittings and drive it around and see if it still makes some noise. I listened to it more carefully today, and the squeak does seem to match up with the rotation of something as it drives. If the zerk fittings don't do it, I'll open up the CVs and put some more grease in there.

 

Yeah basically there’s a tan grease and a black grease. One is for inners other for outers, and it seems to be a lot of confusion about what the difference is.

 

Finally had a chance to crawl under the truck today. Hit all the zerk fittings and they were all pretty full, couple pumps each. Even the slip yoke at the back only took maybe 5 pumps before the shaft was expanding, so I'm pretty sure the suspension was getting some love at least occasionally. Had a better look at the CV boots and they're good, only oil I could see around them was from the valve cover gaskets. Drove up and down my dirt road in 4hi and no change.

Didn't have time to open up any of the CV boots today, so the next time I have time to work on it I'll throw the front end up in the air and try turning the front wheels with it in 4wd and see if I can find the squeak.

 

Clarifying on the squeak. Is it more of a high pitch screech like nails on a chalkboard, a high pitched squeak like a mouse, or a more creaky groan, like a straw dragged thru a plastic drink lid?

 

Sounds similar to blown out bushings. I'd say high pitched creaky groan.

 

All I can recommend is to jack up one side of the truck so the tire is about 1-2” off the floor. Throw a 2x4 on the ground and use it as a fulcrum with a pry bar, lift up and down at the center of the tire while watching the LBJ & UBJ for movement. There should be zero play.

Throw your stock bottle jack under the LCA to put it under tension, get it to roughly ride height. Grab the tire firmly at 3 and 9 o’clock and try to push/pull it like you’re attempting to shimmy it off. Repeat at 6 and 12 o’clock. Repeat at diagonals. Do you feel any play in any of those positions? Hear any squeaks? Again there should be zero play.

Only do this with one wheel jacked up at a time.

 

Will do, thanks.

 

So I was driving around on a friend's property yesterday and I had him get out and listen for the squeak. At first it didn't make any noise, then I cranked the wheels all the way over and it barely squeaked. Think it might just be the CV boots squeaking, it was a lot quieter than I realized and he could barely hear it.

 

CV boots don’t squeak normally.

 

Yup, but until I can get this up on a lift or 4 jack stands, that's my best guess. Really only noticeable at low speed, window open, stereo off, and in 4hi or 4low. As soon as I started driving a little faster or revving the engine higher to climb hills I couldn't hear it anymore.

On the plus side, rainy season is here so I won't be driving with the window down much anymore, so not likely to hear it.

 

Lower ball joints