Front CV Axle rattling, grinding, interference issue...please help

[100sExp]

Over the summer, I did some major (but common) modifications to my 100s. One of the changes was to do a 2.5" heavy load lift. The lift consists of Nitro Gear UCA's, Old Man Emu torsions and springs, Icon 2.5 stage II RR shocks. The upgrade has been really nice but I've now run into a problem and could use some assistance from our knowledgeable community.

After my last desert trip (which everything performed very nicely) I noticed a torn CV boot and grease under the truck. It was the drivers inner boot. I took to my local mechanic for repairs and he replaced both front axles and also the lower ball joints, which were worn.

After picking the truck up, I was noticing a vibration/rattling under acceleration. It didn't occur when I lift off the throttle but the harder I accelerated the worse it seemed to be. I took it back and did a test drive with my mechanic and his initial feeling was that it wasn't coming from the front and felt like a worn U joint. However, after closer examination, he's noticed it is indeed coming from the front axles.

I haven't yet been back to look at what he's talking about but what he says is that the sever angle of the front suspension, while in full droop is what's causing an interference (with exactly what, I can't remember) and the problem. The reason it happens under acceleration is because the weight transfer of the vehicle makes the front lift and this is when it occurs.

Anyhow, he's doing some digging looking for a solution and now I'm here doing the same. Has anyone else experienced this? What's the best way to fix it? Thank you

 

[yeti in ga]

What kind of CV Axles and are you running a diff drop with your lift ? I had some bad vibrations and after replacing both U JOINTS all is nice.

 

[100sExp]

They're stock replacement CV's and yes, I am running the Slee Diff Drop.

 

[abuck99]

When you say "stock replacements" , you mean to say they are OEM Toyota CV axles ?

Did you happen to keep your old CV axles to reboot? You could swap these back in one by one to check which one is vibrating if that is in fact your problem.

Isolating where your driveline vibes are originating is challenging & can be misleading. Depending on your mileage your rear drive shaft ujoints ( output or pinion) could be complaining post lift if your propshaft is not in alignment- (pinion angle correction). Usually that is more noticeable under power/acceleration- not decel. Your front drive shaft Ujoints may be worn as well but these usually aren't affected as much as the rears by lifting unless you have engine or transmission mount issues.

Btw, what are your post lift droop measurements? 50-60-70mm?

 

[Sandroad]

I hate to be the simpleton here, but no vibration before the new axles and vibration after the new axles sure seems to indicate axle problems. I like @abuck99 suggestions about swapping back in the old axles one at a time. And, I'm sure you meant Toyota OEM axles, but, if not, that's likely the problem.

 

[jemsec]

If the axles were OEM, with proper installation of the bearing assembly, you should not expect the problems experienced. If after market cheap axles were used, the change in angle due to the lift would be the issue with after markets. There is a huge difference in OEM axles and the low priced after market axles.

Look at your invoice. OEM should be $500.00+ each plus and after market in the $100.00 to $200.00 range. There you will find your answer.

 

[bigredmachine]

confirm that they are factory, ive had the same issue with other vehicles with cheep aftermarket axles cause a vibration for one reason or another, slightly wrong size, splines just not quite right and not letting the axle seat, or just plain junk.

if your thinking that it may be a u joint in the rear shaft, remove the drive shaft, go for a drive and see if the vibration goes away. no vibration issue, u-joint issue

 

[uHu]

Sounds like it could be the spindle bearings. Are they intact and well lubed with NLGI-1?
The spindle bearing supports the cv shaft through the spindle, and if worn, damaged or dry, it will give vibrations/noise.

 

[H E A V Y M E T A L]

mount a gopro under your car and drive it around.

 

[100sExp]

If the axles were OEM, with proper installation of the bearing assembly, you should not expect the problems experienced. If after market cheap axles were used, the change in angle due to the lift would be the issue with after markets. There is a huge difference in OEM axles and the low priced after market axles.

Look at your invoice. OEM should be $500.00+ each plus and after market in the $100.00 to $200.00 range. There you will find your answer.

Thank you guys for all the feedback. Based upon what I've read, my assumption is that aftermarket axles were used and that is what's causing the problem. I paid $140 each for them, which is much lower than the $500+ Jemsec has said that the OEM ones cost. The front bearings were recently replaced, I doubt that's it. The driveshaft was removed and the truck driven with only front drive, the issue was still there and the U joints looked fine. I wish I would've asked for group assistance a day earlier because perhaps it'd already be fixed but hopefully Monday my mechanic will get back to it. Sure hope I don't have to pay all the wasted labor costs again, Ugggh. I give an update once it's fixed.