1997 LX450 vibration during acceleration

[Bryan72880]

Hi All,

I'm a 1997 LX450 owner experiencing some worsening vibration during acceleration. I've only got 60K on my truck which has been babied it's whole life. I'm not sure if it's a harmonic thing with the exahust system or what? It seems to be getting worse and the dealer is kind of clueless.

Anyone in the central NJ / southeastern PA area that is familiar with 450's who may be willing to give me an expert opinion??

Thanks!!
Bryan

 

[Romer]

Welcome Bryan

This thread is in the repair section of the FAQ for 80/450

https://forum.ih8mud.com/80-series-tech/80904-drive-shaft-pm-drive-train-troubleshooting-faq.html

It sounds like this could help you

 

[Kernal]

Agree with Romer; could be dry U-joints or driveshaft yolks. Do you feel the vibration in the steering wheel or brake pedal? Dry spindle bushings can cause a rumble usually worse when you first start a drive IME; how do your steering knuckles look, dry, rusty? FWIW: as my exhaust system has aged/deteriorated I've gotten a progressively worsening growl/rumble under acceleration. The system has no external holes that I can find, I think the muffler and resonator are just falling apart internally.

 

[Bryan72880]

Romer, thanks for the link! That is super helpful information and I'm scheduled with my mechanic for the replacement of the U-joints, shaft balancing, diff fluid flush, and trans flush tomorrow! I printed out the entire thread so he has it for a reference. Anything else you might recommend at this point?

Kernal, I wonder if my exhaust system may be suffering the same fate. My truck has rather low miles, 60K, but in some cases I'm told that can be a bad thing... i.e. short trips where the exhaust system doesn't heat up all the way to burn off moisture, etc.

I've been going to a dealer and I'm done with them now. I'll be using a private mechanic that I trust from here out.

Any other thoughts?? She's going in 1st thing tomorrow morning for the drivetrain work!

Thanks,
Bryan

 

[Kernal]

I would be a bit surprised if your U-joints were bad with only 60,000 miles, they might be dry if they've never been lubed. IME and from reading here on MUD the original U-joints last 200,000 miles minimum with proper lubrication. The grease fitting on the front U-joint of the rear driveshaft is difficult to get to with a grease gun and in my experience these are sometimes skipped by the grease monkeys, same for the rear U-joint of the front driveshaft; difficult to get a grease gun nipple on the zerk fitting. The axles have to be extended by lifting the vehicle by the frame in order to open up the angle of the U-joint to allow a grease gun nipple to fit into the U-joint to get at the nipple. And then the driveshafts/U-joints have to be oriented where those zerk fittings are facing up. In order to do that you have to put the transfer case in neutral before you lift the rig so that once the vehicle is up in the air (wheels off the ground) you can turn the driveshaft by hand to get it into the proper orientation for the grease gun nipple to fit. Does that make sense?? If you do replace the U-joints IMO only use Toyota parts, something your local dealer will probably not have in stock.

Can you describe the vibration in more detail?

 

[Romer]

I would be a bit surprised if your U-joints were bad with only 60,000 miles, they might be dry if they've never been lubed. IME and from reading here on MUD the original U-joints last 200,000 miles minimum with proper lubrication. The grease fitting on the front U-joint of the rear driveshaft is difficult to get to with a grease gun and in my experience these are sometimes skipped by the grease monkeys, same for the rear U-joint of the front driveshaft; difficult to get a grease gun nipple on the zerk fitting. The axles have to be extended (ie: lift the vehicle by the frame) in order to open up the angle of the U-joint to allow a grease gun nipple to fit into the U-joint to get at the nipple. Does that make sense?? If you do replace the U-joints go with Toyota/Lexus parts; something your local dealer will probably not have in stock.

Can you describe the vibration in more detail?

Mine were bad at 100K, PO took it to the dealer for service regularly

I should note, mine where not bad, but when I lifted the truck, they did not like the new angle and replacing them and balancing the drive shafts took care of it

Bryan - I would also get the shafts balanced

 

[Bryan72880]

Kernal - the vibration is occurring when the engine is under load, most noticably during acceleration. For example, accelerating thru first gear where the shift point may be 3,000 RPM, the vibration is pretty severe between 2,000 - 3,000 RPM. Upon shift to second, the vibration continues thru the RPM range. At highway speed, the vibration is only present when accelerating or depressing the gas pedal to maintain speed. To me it feels like a drivetrain issue... the dealer thought it was harmonic resonance in the exhaust and welded on a vibration damper. Didn't do much of anything.

I'm going to go thru with having the u-joint replacement completed. I told my mechanic that I want to use only genuine Toyota parts and he agreed. He is also going to send the shafts out for balancing so I'll be without my truck for 2 days. I have the center diff lock switch, so we can test with one shaft out if necessary. I took a peek underneath the truck and the phasing is correct on the shafts as currently installed. I'm hoping that it's simply a balance issue and not a more severe problem with the transfer case, etc.

 

[Romer]

Bryan
Most shops mess reassembling the front shaft as its out of phase. Tell your mechanic to mark both sides before seperating to get the splines lined up the way they were along with the correct phase. Course you should make sure it sits out of phase now as that could be part of the issue

 

[Kernal]

Bryan: Let us know how it turns out and what the condition of the old U-joints and slip yolks were (dry, rusted, broken pin bearings?), if the shaft was out of balance, etc. I'm also going to a driveline shop tomorrow to try and diagnose a whine/roar I've been getting under load, just no vibration.

 

[elhombre]

Just a thought, if you know of a driveshaft or drivetrain shop around your town, it really is very easy to remove one driveshaft at a time and take it to them to rebuild it. Buy Toyota u-joints from CDan so you get a good deal and KNOW that you got actual Toyota parts. You may save some decent ching-a-ling doing it yourself. If I remember correctly, it is 12mm socket/wrench to get the 4 flange nuts off at each end of the shaft, and out it comes.

Driveshaft shops have the expensive balancing machine that most garages don't invest in, so they are usually very good at what they do in welding the weights on.

 

[CMY4XGO]

What your describing sounds identical to what my 97 was doing. Just my .02 cents here, but i did all the above recomendations and it turned out to be the rear pinon bearing.

I completely support the method in which your addressing this issue. I only offer my situation to you if the repairs are completed and the end result is the same.

60k? Is that a typo? Incrediable!

How about some pics?

 

[Bryan72880]

Thanks everyone, just dropped off at my mechanic. He's got a printout of this thread and also of the Drive Shaft Troubleshooting thread. I went over everything with him and he is totally on-board with all of the suggestions.

I will give an update as soon as I know anything.

CMY - 60K is a typo actually.... it's 62K I took a few pics with my phone just now.

 

[Titan94]

OoOo purty, if only it wasnt white, too many white 80's . let me know what ends up being the problem, i have some clunks and vibrations that I have been putting off since im going to college, would be nice to get them fixed while im away.

 

[Bryan72880]

Update: Just stopped by my mechanic, and he told me one of the U-joints is bad... "totally bound up" as he says. He also said that it doesn't look like they have EVER been greased.. thank you Lexus/Toyota!!!!

He ordred all new U-joints from Lexus, and unfortunately Lexus didn't understand and delivered 4 new yokes while I was there! Anyway, we will be into next week at this point for the U-joints to come in, and the shaft balancing.

 

[Bryan72880]

Update 2: HELP!! We are back to square one. The u-joints have all been replace with new OEM Lexus/Toyota parts, drive shafts have been balanced, diff and transfer case fluids have all been changed, and we still have the vibration.

Upon looking deeper into the vibration, we have uncovered what appears to be a harmonic vibration originating from the engine itself. Around 3,000 RPM there is a noticable vibration felt by hand on the intake manifold and more noticably on top of the air cleaner housing. We disconnected the air cleaner housing from the body to isolate the vibration and it's certainly coming from the engine.

Next thing we're going to do is take off the drive belts to rule out a vibration from any of the accessories. Other then that, we aren't sure where to go from here. Have there been any known issues with vibration from the motor itself? I'm getting worried that I'm not going to be able to fix the problem economically - i.e. I'm not going to have the engine pulled, taken apart, and balanced.

I'm looking for any suggestions! Thanks everyone!!

 

[Kernal]

Bryan; By harmonic do you mean the rpms are changing up and down a bit when you hold the pedal in the same position?? Is the engine misfiring? Any more information on the vibration? Does it occur when in park, when in drive, idling versus higher rpms? Unusual noises? Water pump going bad? Fan clutch frozen? Crank pulley/harmonic balancer coming apart?? Broken motor mounts, cracks in motor mount brackets?? Does the engine tip/move significantly if you run the rpms up quickly (it does move some normally)? (just tossing out some ideas). Can you make a video clip and post it up on youtube?

Did your mechanic show or give you the old U-joints? Got photos of the dry cups/bearings?

 

[Bryan72880]

Kernal, the engine has a noticeable vibration while in park and revving it up to about 3,000 RPM. The vibration will vibrate you hand off the intake manifold (almost, that's a bit of an exaggeration but not much). When driving and accelerating a shudder is felt while passing thru 12 o'clock on the tach. At highway speed, the vibration is only felt when pushing the gas pedal. With the driveline checking out okay, we're now on to the engine.

The motor does tip when starting but doesn't seem to be abnormal. Also tips when revving fast, but again to me looks normal. My mechanic is going to inspect the motor mounts tomorrow to look for cracks and check the rubber to make sure its not dried out. I'll take a video clip tomorrow morning first thing.

Revving the engine at the shop, it felt as if something were off balance causing the vibration - whether internally in the engine, or on the accessory drive I'm not sure. With only 60K it's hard to imagine that there could be internal engine balance issues. No misfiring was detected. Is the crank pulley/harminic balancer prone to failure?

I think my mechanic still has the u-joints and if so I'll take photos. Very frustrating at this point because I was so hopeful that the driveline work would fix the problem.

 

[Kernal]

There are other Mudders who know the engine much better, but don't recall ever reading about anyone having a problem with a balance problem due to internal engine components going bad. Could the problem be the engine running rough causing the vibrations?? Any codes? The engine harness is known to get fried due to it's close proximity to a hot EGR pipe, then all sorts of things can happen and one of them is burned/shorted wires to the fuel injectors. Don't know how often the harmonic balancers delaminate, have to wait for someone else to chime in. Does your mechanic have much experience with Toyota's or Landcruiser's? Reason I say that is that you would think a good mechanic would have picked up on an vibration from the engine versus the driveshaft IMHO.

 

[Bryan72880]

The check engine light isn't on so I guess it's not throwing any codes? When I took the LX in, I told my mechanic I wanted him to do the u-joints, balance, fluids, etc., based on what I thought was the problem and from all I had read on the forum. As it turned out, one of the u-joints was bad so it wasn't for nothing. So I didn't really give him the opportunity to diagnose the problem... I tried to for him LOL

I wouldn't say that he has specific knowledge of LC's and all their ins and outs, but I have faith that he is putting his best effort into figuring out whats going on. Honestly you guys have been a huge help and a wealth of information and I'm very grateful for the input! I'm going to relay all of the info on the wire harness, etc. I should know something more tomorrow and will be back on here for sure!!

 

[Kernal]

IMHO I would take it to someone else, probably a Toyota dealer, even if just for a second opinion about the engine vibration. They may charge you one hour labor and you could get closer to a diagnosis. If your current mechanic said the engine maybe needed rebalancing that would be a red flag for me. I forget, when did this all start??