Buying Lifted 80 - Noise in front end, Need help! (2 Viewers)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Joined
May 6, 2020
Threads
5
Messages
9
Location
Iowa/Texas
Hey guys,

I decided to buy a lifted LX450 this week and after getting up to highway speeds there was a grinding noise only above 60 mph that seemed to come from the differential or drive shaft. It felt like a vibration and would cut in and out. The dealer is now trying to suggest fixes and I feel it is caused by the 4.5-inch lift since the drive angles are pretty severe. There could be a problem with u-joints and I am wondering what is needed such as dc driveshaft or castor correction.

Please give any input on what the noise could be and how we can facilitate a healthy lift, thanks in advance to you guys!
 
1st, get your caster checked.
Then we can provide insight for the next check.
 
Also provide photos of the LX drivelines for angle access meant front and rear including the ends of both drivelines at the diff’s and transfer case. A photo showing the entire vehicle from the side will also be helpful to get the answers you need.
 
CBE71685-B91F-49BA-AF7F-82D53C9F0291.jpeg


7EC2698D-31CC-4BAD-98A8-EC512F965728.jpeg


EEC001A6-9F32-4FB2-932C-A3D62F89595C.jpeg
 
I honestly don’t have many, and I am leaving the dealer and flying back home now - original plan was to drive it 2000 miles back home but that is not happening anymore. I can get more images, but it looked like the driveshaft was pretty steeply connected to the transfer case and there was a good amount of sway on the highway. We even swapped drive axles from another 80 and the noise was still present.
 
Ok, well, the pics need to be from the side so angles can be seen. If the LX has a CDL button on the dash, you can remove the front driveline and lock the center diff to drive on the rear only. It’s quite likely that your problem is the front driveline vibrating.
 
That's a fresh lift or someone polished the coils and shocks and resprayed them :)

Front sway bar isn't dropped as it should be for clearing the front prop shaft on droop. Prop shafts look very dry - at least pump some grease into the ujoints and a few pumps into the slip joint nipples.

Given the 'newness' of the lift, I'll bet it was tossed on to make it all look manly, but nothing else was done to address the lift. New ujoint angles due to new lift. Lot's of possible issues.

As above, lock the center diff (with no CDL button) you can toss it into low range, get the center locked and then pop out the appropriate fuse. Drop the front prop shaft and run on the rear only.

Or it could be the head gasket getting ready to blow (mud humour).

And welcome :flipoff2: (official mudgreeting).

cheers,
george.
 
I honestly don’t have many, and I am leaving the dealer and flying back home now - original plan was to drive it 2000 miles back home but that is not happening anymore. I can get more images, but it looked like the driveshaft was pretty steeply connected to the transfer case and there was a good amount of sway on the highway. We even swapped drive axles from another 80 and the noise was still present.

Any pictures from the ad? Even that can get us close.


The more you lift, the more you need to correct castor... the more you increase caster, the more you increase the driveline angles. Assuming you have at 2.5" lift, and there isn't a frame side radius arm drop, the pictures make it look like you have no castor correction, so you are likely sitting at around -1 degree with spec being +3 degree (+/- 1 degree).

With too little caster, it will feel darty and wandery... that could be some of the sway you are feeling.
 
Castor correction and a part time kit
 
The bad thing is those pictures are with the LC on a lift. So the angle is exaggerated, if you can get pictures of the drive lines while the wheels are supporting its weight that would give us a better idea.

The front drive line is notorious for growling after you lift an 80. Mine growled for years before I replaced it with one from Tom Woods a double cardan which helps with the growling/vibration you were hearing.

The slip joints on both the front and rear drive lines look pretty dry. Have them grease the slip joints and u joints to see if that helps eliminate some of the growling.

@landtank mentioned that the rear drive line looked out of phase, manufacturers shipped their vehicles with the slip yokes installed differently for a reason. I was told by Kevin that is no longer with us changing up the phase of your front drive line could make a difference in the growling.

Mentioned above Toyota shipped some LC with their drive lines out of phase, which can be solved by dropping the drive line with the slip joint and clocking it into correct position.

iu


As far as swaying. That could be a few issues, higher center of gravity, softer shocks, etc.
 
Also, depending on the lift, the front shaft starts acting up. Had to replace mine due to the same-ish symptoms you're talking about. I'd also correct the rear like landtank is suggesting.
 
I just increased the ride height of my 80 recently and am chasing down a *little* vibration/growling after caster correction. As most have said, it's hard to tell while the suspension is unloaded on a lift, but you will definitely want to extend all of your brake lines if you plan on wheeling it at any point.


1679063978645.png
 
From what I have learned (thanks to you guys!), front sway bar needs to be dropped, castor correction might be needed and the rear drive shaft should be rephased. Does this also require the DC driveshaft to be installed and should I look into aftermarket control arms?

Also, it seems like the cause of the grinding noise could be the transfer case instead of driveshaft since it only occurs above 60 mph and varies with throttle input.
 
From what I have learned (thanks to you guys!), front sway bar needs to be dropped, castor correction might be needed and the rear drive shaft should be rephased. Does this also require the DC driveshaft to be installed and should I look into aftermarket control arms?

Also, it seems like the cause of the grinding noise could be the transfer case instead of driveshaft since it only occurs above 60 mph and varies with throttle input.
Without knowing how much lift, hard to say.
 
Was told 4.5 inches, seems more like 3.5 at the moment and may add some body armor causing it to drop
 
From what I have learned (thanks to you guys!), front sway bar needs to be dropped, castor correction might be needed and the rear drive shaft should be rephased. Does this also require the DC driveshaft to be installed and should I look into aftermarket control arms?

Also, it seems like the cause of the grinding noise could be the transfer case instead of driveshaft since it only occurs above 60 mph and varies with throttle input.
Hope it’s not your transfer case.
I gather that castor correction for this much lift does require replacing the control arms with aftermarket hardware. Delta Vehicle Systems - FJ/FZJ80/LX450 Caster Correcting Front Radius Arms - https://www.deltavs.com/all-products/fj-fzj80-lx450-high-clearance-caster-correcting-front-radius-arms

You could try the no cost suggestion of removing front driveshaft to see if it’s responsible, in which case a custom front driveshaft might be the ticket.
Or just remove the lift if this would be adequate for your intended use (or ego😜).
 
Castor bushings or notch the arms. Need front and rear Sway bar drop brackets. Front and rear diff breather tubes need extensions. Brake lines need to be extended. Also the rear parking brake.

gotta love the sellers of off road crap who just sell the shocks and springs but TRUELY FAIL at mention, adding or calling out all the other tid bits to run a proper lifted 80
 

Users who are viewing this thread

Back
Top Bottom