LX470 Transmission whine (1 Viewer)

[AlpineAccess]

Have you removed the front driveshaft, engaged CDL, and taken it for a drive? That should be part of this process.

Do you have any noise while at idle? Change in noise from Park to Reverse, Neutral to Drive?

 

[LanghorneLX]

Have you removed the front driveshaft, engaged CDL, and taken it for a drive? That should be part of this process.

Do you have any noise while at idle? Change in noise from Park to Reverse, Neutral to Drive?

No noise at idle. No noise switching or staying in other gears at idle.

wow ok do removing the front driveshaft and locking the diff. What does that rule out, the front diff? I think I am going to check the front diff and xfer fluids this weekend and then considering what you are saying, but I am not great with these drive trains so I am scratching my head a little with the test you proposed. Thanks for the suggestion!

 

[thebeedeegee]

No noise at idle. No noise switching or staying in other gears at idle.

wow ok do removing the front driveshaft and locking the diff. What does that rule out, the front diff? I think I am going to check the front diff and xfer fluids this weekend and then considering what you are saying, but I am not great with these drive trains so I am scratching my head a little with the test you proposed. Thanks for the suggestion!

I belive you are just removing the load from the front diff by doing that. When you remove the front drive shaft the engine won't load the front diff, you then have to push the CDL so you can drive the truck to test. Maybe with no load on the diff the noise stops

If you didn't lock the CDL the center diff would put power to the path of least resistance (the front shaft since it had no load) with the CDL locked power is split between front and rear shafts instead

 

[AlpineAccess]

No noise at idle. No noise switching or staying in other gears at idle.

wow ok do removing the front driveshaft and locking the diff. What does that rule out, the front diff? I think I am going to check the front diff and xfer fluids this weekend and then considering what you are saying, but I am not great with these drive trains so I am scratching my head a little with the test you proposed. Thanks for the suggestion!

Exactly, would remove load on diff while deceleration is happening. If you have bad gear lash or bearings, removing the load will either remove the noise or alter it significantly.

CDL needs to be on as noted, because you want to lock output to the rear wheels and not have the vehicle trying to send power forward without the driveshaft in. On full time 4x4 systems this is a very common test.

You can drive around like this in 2wd with no issue.

 

[LanghorneLX]

I belive you are just removing the load from the front diff by doing that. When you remove the front drive shaft the engine won't load the front diff, you then have to push the CDL so you can drive the truck to test. Maybe with no load on the diff the noise stops

If you didn't lock the CDL the center diff would put power to the path of least resistance (the front shaft since it had no load) with the CDL locked power is split between front and rear shafts instead

Makes perfect sense now. Thanks for the follow up! You guys are great on this forum. Much appreciated.

 

[AlpineAccess]

Makes perfect sense now. Thanks for the follow up! You guys are great on this forum. Much appreciated.

Just keep in mind that if removing the front driveshaft reduces or eliminates the noise, it is just isolating the problem to the front end (and/or your transfer case). This helps to narrow the focus by dividing the vehicle in half forward of the transmission. You then keep dividing things in half through troubleshooting until you're left with one or two options for repairs.

 

[LanghorneLX]

No noise at idle. No noise switching or staying in other gears at idle.

wow ok do removing the front driveshaft and locking the diff. What does that rule out, the front diff? I think I am going to check the front diff and xfer fluids this weekend and then considering what you are saying, but I am not great with these drive trains so I am scratching my head a little with the test you proposed. Thanks for the suggestion!

I changed the front diff, rear diff, and transfer case fluids with mobile 1 75w-90 synthetic. The whine is still there. Lots of gum on the front diff drain plug, but it seemed normal.

I will do the tranny drain and fill several times next weekend.

 

[LanghorneLX]

UPDATE! I changed the fluid in my rears and transfer case with Mobile 1 75-90. I also drained and filled the transmission 4x (it was red again at the end) and loaded the tranny in all gears between drains. At the end I got it to 100degrees F (measured with a IR thermometer) and it was not running out so added 1/2 quart and it started dripping out. I let it run for a little so the new fluid heated up and expanded and then checked again at the check plug and let it run out until it was not a continuous stream (it was now at 102F). Shifts great. No new issues. It was the first change in all the fluids and I have 158K miles on her. Long story short, the Preventative maint is done and cost me $230 (I got a pump) and used Toy WS fluid (prolly not needed). The whine in the front rear is still there when I decelerate same as before. It goes away when I go into N. It doesn't matter if I am in OD or D or if the caris warmed up after a long drive. I first recall this whine about 5Kmiles ago and got worse since then - let's hope it doesn't continue to get worse. I can barely hear it with the radio on, and there is no vibration. Time to live with it!

If it doe get worse I will pull the front drive shaft and lock the center diff and see if that helps. If it helps I will rebuild the front diff. Make sense guys?

Thanks to everyone for your help. Espectially 2001LC - he is the man.

 

[LanghorneLX]

UPDATE! I changed the fluid in my rears and transfer case with Mobile 1 75-90. I also drained and filled the transmission 4x (it was red again at the end) and loaded the tranny in all gears between drains. At the end I got it to 100degrees F (measured with a IR thermometer) and it was not running out so added 1/2 quart and it started dripping out. I let it run for a little so the new fluid heated up and expanded and then checked again at the check plug and let it run out until it was not a continuous stream (it was now at 102F). Shifts great. No new issues. It was the first change in all the fluids and I have 158K miles on her. Long story short, the Preventative maint is done and cost me $230 (I got a pump) and used Toy WS fluid (prolly not needed). The whine in the front rear is still there when I decelerate same as before. It goes away when I go into N. It doesn't matter if I am in OD or D or if the caris warmed up after a long drive. I first recall this whine about 5Kmiles ago and got worse since then - let's hope it doesn't continue to get worse. I can barely hear it with the radio on, and there is no vibration. Time to live with it!

If it doe get worse I will pull the front drive shaft and lock the center diff and see if that helps. If it helps I will rebuild the front diff. Make sense guys?

Thanks to everyone for your help. Espectially 2001LC - he is the man.

Hi! Update 10/2021. The whine (whirling) on deceleration got much worse and is now audible from just 10mph to 0. It started just over 50mph. So I pulled the driveshaft and the noise is gone!

I don’t know anything about diff maintenance or adjustment or rebuilds, but I assume there is some other process I can do to troubleshoot. Also it’s still possible it’s in the transfer case. I am fairly handy and don’t mind learning more. I assume there are several bearings that I can try to change from the exterior? Anyone have an idea what to try next?

 

[digitalmarker]

Hi! Update 10/2021. The whine (whirling) on deceleration got much worse and is now audible from just 10mph to 0. It started just over 50mph. So I pulled the driveshaft and the noise is gone!

I don’t know anything about diff maintenance or adjustment or rebuilds, but I assume there is some other process I can do to troubleshoot. Also it’s still possible it’s in the transfer case. I am fairly handy and don’t mind learning more. I assume there are several bearings that I can try to change from the exterior? Anyone have an idea what to try next?

Did you get this sorted out? I have the exact same symptom and trying to figure out if it's the front diff or the transfer case.

 

[LanghorneLX]

UPDATE! After removing the front driveshaft, locking the center diff, and driving the whine the noise went away completely! I changed the ujoints in the front driveshaft for good measure and then reinstalled, but the noise came back in all it's glory.

I took to a transmission 4x4 shop a couple towns away (needed to search for a good one) and they diagnosed as a front diff. I found dealer priced at $2200 for parts. Used on Ebay (risky at $1200+300 to 500 for shipping).

Is the 2006 Toyota LC front diff the same as the 2006 LX? I am wondering if I can game the dealer system that way and just get it lower cost at toyota....

Thanks for your help!

 

[LanghorneLX]

UPDATE! I need to replace the front diff. I pulled the front driveshaft and locked the center diff then drove and the noise went away. When it was out I replace the ujoints for good measure, but the noise returned when I reinstalled. I took to a transmission 4x4 shop two towns over to find a good shop and they found a little metal in the fluid (which I changed 18month ago).

I found a front diff part number for a Landcruiser seems to match the pn for my LX470. So I shopped and found new for 1500-2500 depending on the dealer (toy tended to be less).

Any ideas on what other maint or adjustments I should do when I replace? I recall someone explaining how to reset the torsion bars (ride ht). My LX has 166K miles. Also there are some diff mounts that some people struggle with, so I will be sure to inspect those and replace as needed. Other ideas/thoughts?

Thank you all!

 

[digitalmarker]

UPDATE! I need to replace the front diff. I pulled the front driveshaft and locked the center diff then drove and the noise went away. When it was out I replace the ujoints for good measure, but the noise returned when I reinstalled. I took to a transmission 4x4 shop two towns over to find a good shop and they found a little metal in the fluid (which I changed 18month ago).

I found a front diff part number for a Landcruiser seems to match the pn for my LX470. So I shopped and found new for 1500-2500 depending on the dealer (toy tended to be less).

Any ideas on what other maint or adjustments I should do when I replace? I recall someone explaining how to reset the torsion bars (ride ht). My LX has 166K miles. Also there are some diff mounts that some people struggle with, so I will be sure to inspect those and replace as needed. Other ideas/thoughts?

Thank you all!

Do the axle seals and the rear pinion seal while you have it put, and definitely do the front bushing and the rest of the bushing arms.

 

[bmxben]

I had the same issue, 2000 LX470. The bearings in the front diff had to be replaced. Got it diagnosed & repaired by LandCruiser Specialist in Austin. Ran smooth after it was done. Hope this helps, cheers!

I'm having the same issue except mine doesn't go away if I put it in neutral. What shop did you go to in Austin? I'm just north in Georgetown.

 

[martinezstephen]

I'm having the same issue except mine doesn't go away if I put it in neutral. What shop did you go to in Austin? I'm just north in Georgetown

Hey there, give the team at Landcruiser Specialist a call. They were booked out for a while a few months back when I had some work done but I would call them and get on the schedule. They will get it done right the first time, cheers!