Dying front diff in my 2006?

[nissanh]

IF you got no problems in the front drive shaft, don't do anything other than regrease the U-joints and splines. The front drive shaft pretty mush spins as opposed to the rear, which spins as well as move up and down with the axle movement. The rear drive shaft is the first thing to fail, especially the rear most U-joint. Buy OEM U-joints else leave it as it is.
Post a picture of the complete front drive shaft so I can see whether it is out of phase or not.

 

[SlowBuild]

 

[SlowBuild]

This is from the Driveshaft FAQ by Romer:

 

[SlowBuild]

My thought was this: if shaft is out of phase, it may be balanced that way or not. Once I fix it, it may be back in balance or may still be out or may become out. Could it hurt to balance it just to be sure. I think my diff is likely toast and causing some front end noise but it's likely that the shaft/u-joints may be contributing. This FAQ thread convinced me it might be worth a couple hundred bucks to start new:

Proper Drive Shaft Maintenance

A lot of the problems originate with the Drive Shafts and doing the below maintenance may save you a lot of time and trouble. These maintenance steps will usually correct the clunk (Grease in the spline) or Grrrrr (U Joints)

Note: You don't need to do all this maintenance on the drive shafts at the same time. If you have a Center Diff Lock Switch (CDL), you can drive with one shaft with the CDL engaged. This will allow you to have both shafts rebuilt without any down time on your truck

The shafts are similar except the Rear is longer and is in phase. Looking at the picture below we can see both shafts have yokes, U Joints, Dust Cover, Spline and Shafts.

Common Clunks and Grrs are caused by faulty Yokes or U Joints, Unbalanced Shafts, not enough grease in U Joints or too much grease in the Spline.

The Front Shaft is "Out of Phase", note the ears on the front yoke and rear yoke are 90 deg offset

The Rear Shaft is "In Phase" note the ears on the front yoke and rear yoke appear to be lined up. One of the common causes of these drive shaft woes is the Front Shaft is "In Phase" when it should be "Out of Phase". OR, The Rear Shaft is "Out of Phase" when it should be In. If you take it to a drive shaft shop, make sure you are clear on the phasing before they balance it.

If you want to get your drive shafts in top condition perform the following:
- Place Paint marks on the flange yokes and the differential. case flanges so you can install the shafts back in the same manner.
- Remove both shafts (or do one at a time if you have only one vehicle)
If you have a CDL switch you can drive with one drive shaft out if the switch is engaged with no issues. This will allow you to do one shaft at a time and still drive your rig
- Inspect shafts for damage, if you see some serious damage, then take to drive shaft shop and have repaired.
- Verify they are oriented per the picture
- Clean off an area were the dust cover mates over the propeller shaft and draw a line with white paint so you can re-orient them back the same way.
- Remove the dust cover of the propeller shaft
- Using Brake cleaner, long sticks, etc. clean all the old grease out of the spline and dust cover. make sure both halves are dry and clean.
- Take apart the shafts and clean out the splines
- Take the Shafts to a Drive shaft shop and have them replace the U Joints with Toyota OEM Joints and balance the shafts. Make sure the phasing is correct before balancing.
- Re-install drive shafts. Grease the zircs on the U Joints until it oozes out of the U joint.
- Take it for a drive and verify everything is operating correctly. The only thing we didn't touch was the yokes, which do go bad, but rarely. The Drive Shaft shop should have checked this.

Or you can use Semlins thread how to replace the u-joints in your 80 (Semlin Dec 2005) I would still take it to a shop and have it balanced.

Cost for me (Including OEM U Joints) was $197 per shaft replacing the U Joints and balancing.

When I had my shaft problem, the Rear U Joints seemed fine when cool, i.e. at the shop. But when Slee drove it around and took it off while it was warm, you could feel a dead spot in the U Joint that went away when it was cool. My recommendation is to change all the U Joints and have it balanced at the same time even if the shop says you don;t need to.

Another approach is 'if it ain't broke ,,,' I guess I could throw it all back together with the new diff and if there are still any issues it's easy enough to pull the shaft and rebuild/balance it.

 

[duggy]

It is not good to move the flange up and down (vertical to the ground). The easiest way to fix it is tighten the pinion nut until you feel no free-movements up/down and in and out. When it is tight both those movements should stop. So if you plan to tighten the nut, turn it about 5 degrees and check the free play then move on until there is no free play. Drain the gear oil and refill at least 2-3 times between 1-2 mile drives to get all the metal filings out. This could be the reason why your oil-seals are failing very often.

The best way is costly as it might need new ring gear, pinion, side gears etc., You can find a used diff on ebay but check the ratio. Also a Toyota diff guru in AZ is highly recommended to fix these diffs.

NO. STOP. DO NOT DO THIS.

The pinion nut is backed by a crush sleeve and if you tighten it, you will increase the preload on the ring and pinion and destroy both of them.

The best way to diagnose this issue is to first pull your drive shaft and also pull your front drive flanges to see if you can isolate the noise to the differential. Do this and report back.

 

[Romer]

h

EDIT: That FAQ is from the 80's forum, not the 100's forum. I don't have a 100's FSM or I would look it up for you

 

[SlowBuild]

Thank you Romer. I need to filter my search results better!

Does anyone know proper phasing for front drive shaft on a 2006 LX470?

duggy, thanks. I had read a thread discussing how bad/less bad it is to tighten the pinion nut to remove play. Since I'm looking for a proper fix at this time I don't think I'll mess with it. I'll try to isolate the diff this weekend.

 

[abuck99]

The 80 front DS phasing is different to the 100. I noticed that your u-joints(caps on the spiders) look pretty dry- FWIW those want to be greased every 3k to 5k miles.

 

[nissanh]

Your drive shaft is in the proper phase.

 

[SlowBuild]

Thanks y'all, I guess I was looking at the wrong diagram.

 

[SlowBuild]

After cleaning off all the grease and oil from under the front end last week, I went out and drove 60-80 miles this weekend, around town and up the mountain and back. It's clear there's fluid leaking from the pinion seal and from the right front axle seal. I also checked again and there's definitely play in the pinion shaft (in/out, up/down).

The dealership just replaced that axle seal about 200 miles ago. Is there a chance it blew out already because of shrapnel in the case or did they just screw up the install by seating it too deep or something?

 

[Riaz]

I'm pretty sure it was diff fluid because it stopped dripping after the dealer replaced my axle seal. My water pump was still leaking at this time but the coolant reservoir level wasn't getting any lower and I think the coagulating coolant sealed itself up. I could see it congealed on the front of the engine but it was stable like that for probably 7k miles before I had it repaired. I had the pump replaced along with serpentine belt/timing belt etc. about a week after the axle seal was done. The squeal sound only began in the past two weeks, immediately after new belts were put in, and it's been getting more persistent. Maybe it was coolant dripping but I doubt it. I think the drip is unrelated to the squeal sound, of course I could be wrong.

 

[tacoduck]

After cleaning off all the grease and oil from under the front end last week, I went out and drove 60-80 miles this weekend, around town and up the mountain and back. It's clear there's fluid leaking from the pinion seal and from the right front axle seal. I also checked again and there's definitely play in the pinion shaft (in/out, up/down).

View attachment 1543637 View attachment 1543638

The dealership just replaced that axle seal about 200 miles ago. Is there a chance it blew out already because of shrapnel in the case or did they just screw up the install by seating it too deep or something?

I would take it back to the dealer. Looks like they did a s*** job.

 

[SlowBuild]

I considered it for sure but by now I think it's more than just a leaky axle seal, there's not much to gain by having them redo it. The pinion shaft has play and the pinion seal is leaking as well. I wish they had diagnosed it a little more carefully so I could have saved the money and I'll discuss that with them but at this point I feel better tackling it myself. As I write this I'm in the process of dropping the diff and the front axles. I'll rebuild the axle assemblies, have a look in the diff, and post here what I find. I'm hoping the grinding I hear is the diff gears and when I have it rebuilt it will all be behind me. The loud squeal definitely stopped when I removed the drive shaft.

I take this as a chance to know the truck better, a lesson learned about doing a more thorough evaluation before I buy a crappy truck (even if it is a land cruiser) and maybe an opportunity to add a front locker.

 

[SlowBuild]

Here's what the drain plug and diff fluid look like:

Fluid was changed about 7k miles ago and again (I hope) when the axle seal was a replaced a few weeks and maybe 300 miles ago. I've never done this before but it looks like a lot of metal and dark fuel for such a short time.

 

[SlowBuild]

Also: PLEASE HELP!

My upper ball joint castle nut is seized to the bolt.

I soaked it with PB Blaster before even checking how tight it would be. Then I loosened it with a 24" breaking bar (but gently) and it came free a lot more easily than I expected. I then went at it with a ratchet and the whole knuckle began to drop as I loosened the nut the first few turns (I didn't expect it to). Then it spun and spun and didn't do anything. So I turned it with an open wrench to have a look and sure enough the bolt is turning with the nut.

Is there any fix for this or do I have to cut it?

I put a jack under the lower arm to catch it in case it falls when it comes loose.....

 

[SlowBuild]

I got it off by patiently turning. The bolt would turn part of a revolution with the nut then it would loosen a little. Eventually it would come loose. This is the side that was just done so maybe the ball joint was just already loose. I didn't really have to hit it like I did the other side to drop it loose.

Still, I can turn the passenger side ball joint by hand just by grabbing the threaded end with my fingers. The driver's side I can't. Is my driver's side just tight or is my passengers side need replacing? And if it is broken, is there a chance the dealership broke it? They destroyed my abs sensor and told me I'd need a new one soon because it was seized on. I took a look at it and reassembled it straight away. I disconnected the top clip in the engine bay instead.

 

[SlowBuild]

I've removed my front drive shaft, front diff, and front axels.

I'm taking this opportunity to clean off and spray everything I can to prevent future rust, then I'll reconnect the ball joints, calipers, and abs sensors so I can drive until I get the diff back.

Does anyone know a good way to seal the inboard end of the drive flange where I removed the axle? Or should I remove the whole flange? I plan to repack the bearings before I reinstall the axels later so I can clean it all out then but I'd rather keep it as clean as possible in the meantime.

 

[78f150tx]

Bump. Any updates?

 

[SlowBuild]

I ordered a front diff with TJM locker from JT. It hasn’t been shipped yet. I was warned it would likely be a couple of weeks. I didn’t get compressor or related install accessories yet I’ll wait to save up more funds. When diff arrives I’ll send back my old one as a core. I’ll open it up first just out of curiosity and post pics, I haven’t done that yet. It feels gritty and sounds rough now when I turn the pinion flange by hand with the oil drained and the axles out.

I ordered new oem cv axle assemblies. I’ll try to sell my old oem reman axle to CVJ as a core and I’ll keep the after market axle and reboot it as an emergency backup. Neither one was giving me problems but both appeared worn and I don’t know how long they were in there.

I also plan to replace swaybay links, diff mount hardware, hub flanges (I’ll have my old ones machined to remove splines in case I ever have front diff or axle issues in future), flange seals, axle seals, bearings, etc. I have all the parts for these but I’m waiting on the diff.

I think I should order new cone washers just in case and new inner snap rings for the axles, it doesn’t look like they were included with oem assembly.

I bought new u-joints and took the front drive shaft to a driveline shop to have them installed and check for balance but I was told there that the old joints were in great condition and there’s no need to replace. I then decided to skip the balance check as well. If I have any problems when I throw it all back together I’ll worry about it then. I might be going a little overboard on the baseline pm but in this case I feel like ‘if it ain’t broke...’.

While I’m waiting for new diff to arrive I’ll replace heater T’s, clean MAF, clean throttle body, replace sway bar links, open diff and inspect, try to install techstream, and prepare for an AHC refresh so I can get started on that once the truck is back together. I should get to this over the next week or so.