TSB 0250-12. Anyone had it done with good result?

Sorry for bringing back the old subject. I let my kids use the car for 3 yrs and stopped monitoring the forum until recently . Now I have the car back and feel the clunk when lift my foot off the brake. I am sure it didn't happen the first 6 months after we bought it. I searched and searched and I didn't see if anyone mention bringing the car to dealer for this tsb and report any results. I brought the car to the dealer and they said it's normal. The tech told me changing out the drive shaft won't fix anything.

So, is it true that its cause is the the axle wrap (seems like it based on my search) and nothing can be done? I retorqued the u-bolts. Mine has 4 leaf springs.

thx

 

I have a similar problem. 2013 4 cyl Prerunner - my truck has always shifted a little harsh, and started exhibiting the "clunk" when coming to a stop. I won't go into the sad details on several trips to 2 different dealers, but yes, they will tell you "it's normal" - everything that has ever happened on my truck was "normal" for the dealer until it got fixed. Well, the clunk is not normal. I am pretty sure on my truck it's the splines on the driveshaft binding. The clunk is when the splines finally start sliding axially, either at stopping or when driving off. I recently found that if I move the driveshaft around a bit then the clunk goes away for a bit, and the truck shifts nice and smoothly. Until it comes back. I will wait until it comes back again and try again to get the TSB done...we'll see. I think you should go back and insist on going through the TSB with your dealer. If your truck a) is covered by the TSB and in stock condition b) exhibits the clunk and c) all drivetrain mounts and transmission mounts are properly torqued you should qualify for a driveshaft replacement. I will update this as soon as my clunk comes back and I visit the dealer again.

 

Thx for the info. Sorry for the late response. Not sure why I didn't get any of the notifications. I don't know what the splines is and what it does. I'll look it up. The tech did mention something about it. I did torque the spring leaf u-bolts up to 70 ft-lbs and now it acts differently. The clunk is now not as bad as before but instead of just happening when I lift of the gas, it now happens when coming to a stop, too. Since mine is a 2010, I don't think dealer will look at it again. How do you move the drive shaft around?

thx

 

The splines are basically a slip joint in your driveshaft. The first photo in this thread has an arrow to that joint - a similar issue being discussed there: https://www.tacomaworld.com/threads/how-to-reg-cab-rear-driveshaft-flip.191798/

These joints had to be greased regularly on previous models and had a grease fitting for that purpose (Tacomas but also other trucks/RWD cars). For a few years now many manufacturers have used "no maintenance" slip joints. There are many cases of these joints getting stuck, or not moving smoothly, including on Tacomas. The slip joint is necessary since the driveshaft's length changes as you drive. This is caused by a number of things, including springs being depressed as you go over bumps/load the back of the truck, overall flex in the chassis, movement of the engine/transmission (they are mounted with some flexibility to reduce vibration). But the biggest factor is the rear axle actually rotating, the infamous "axle wrap". The axle is held in place basically by springs. As you apply torque to the wheels the entire rear axle rotates a little bit. It's inherent in the design. Here is a good example showing the axle rotating (it's on a Jeep, but the basic design is the same) https://www.youtube.com/watch?v=Ny33NtNdFOE

Axle wrap can become more pronounced if you modify your vehicle, for example larger tires. Some people reduce axle wrap significantly by adding anti-rotation bars (traction bars, ladder bars) to the rear axle, essentially holding the axle in place and avoiding rotational movement.

What I think is going on when you feel the clunk is the following: every time there is torque applied to the rear wheels, either through acceleration or braking, the axle rotates a little, as it should. If your slip yoke slides smoothly, no issue. But if it's binding it gets stuck temporarily and I imagine puts stress on the drivetrain axially. Whenever there is a change in the movement of the rear axle, or a change of torque within the driveshaft, it can release suddenly, ending up in the clunk. For me it's also in between gears shifts. When I accelerate, the driveshaft is torqued, slight binding in the slip yoke. Now the transmission shifts, and for a short period of time the torque is reduced, resulting in the slip yoke releasing suddenly - which makes my shifts feel harsh since I get the mini-bump in between gears. When you come to a stop, same thing: you brake, torque applied from the rear wheels to the axle, axle rotates, slip yoke is binding. All good, until you come to a stop - the torque is reduced and at one point the joint releases suddenly, resulting in the clunk. I read some people experience this just before a stop (I think that's then the transmission goes from braking with the engine to idling), for me it's just after the truck stops completely.

I can imagine torquing the u-bolts could have a small impact on axle wrap - I know that one of my dealer visits found nothing wrong (yeah yeah, "it's normal"), but they did re-torque the u-bolts and my clunking was actually reduced for a bit. I still think that's only affecting the rear axle movement but not the main driveshaft issue. The TSB also calls for this - test drive, then check torques on drivetrain, then check torque on transmission mounts, test drive, if still not fixed - replace propeller shaft.

The best way to move the splines in the slip yoke around is of course to drop the driveshaft, remove the boot and separate the 2 parts of the propeller shaft. I found an easier way to check though. When mine gets really bad, I can put the truck in park and move the rear wheels by hand back and forth a few times - sort of rocking the truck back and forth. While it looks and feels really silly, it puts some torque in both directions on the axle, moving the differential up and down and the slip yoke in and out. Be careful though, you are basically putting stress on the parking pin inside the transmission - not sure how strong they are, but you don't want to overdo it. After I do this, my truck shifts like butter and all clonking is gone - at least for a few days. Again, this should only be used to diagnose it, it's not a long term solution. If you can do it with a friend, get under the truck and watch the differential move up and down - moves quite a bit, and you can see the rubber boot getting shorter and longer. TW members please feel free to correct me or suggest better ways other than dropping the driveshaft.

The TSB for this is valid for 60 months or 60k miles, so you may or may not be covered. If you are no longer covered, then I would not even play around with it - I would drop the driveshaft (disconnect at the differential - mark the location before you remove it), remove the boot (also mark it's location), separate the 2 parts, clean and lube, and put the boot back on with zip ties or hose clamps. I am still trying to get the TSB done on mine, which is why I don't want to take it apart in order to keep the warranty intact. Right now, my truck works fine (also changes with temperatures - if it's hotter it seems to be worse), so I need to wait until it's very noticeable to avoid the typical "it's normal" response at the dealer.

Hope this helps - sorry for the essay, this has been the single most frustrating thing for me with this truck, and I am pretty close to giving up on the warranty and fixing it myself.

 

Thx for the detail explanation. I did some search, too and yesterday got under my truck (non-4wd) to look for the boot expecting to see the boot like the link you posted above. Mine looked nothing like it. The part where the shaft joins the trans, has something like a cylinder shape boot with no clamps. I wonder if that's the new boot for 2nd generation and if it's even accessible.

 

The slip yoke is located at the rear end of the drive shaft. Between the rear differential and the center bearing. Left is the front of the vehicle (transmission) right is the back (diff). Slip yoke is between B and C, where the 2 arrows point towards each other. Center bearing is the bracket to the left of the "B".


I have a 2013 Prerunner double cab short bed. I think the design should be the same as yours. I think the regular cabs don't have a center bearing, but the TSB is for 2005-2012 MY 2WD Tacomas with automatic transmission. The part numbers seem to cover model years 2005-2015. In either case, there should be a rubber boot with corrugations and metal straps holding it in place. I think the pre-2005 Tacomas did not have a rubber boot, but did have a grease fitting. If you cannot find it, maybe you could take a picture of the section between the center bearing and the rear differential.

 

Nice diagram. Thx. I think between b and c was the area where I didn't focus due to some blockage of the side view. I was concentrating on the area just between the A and the trans. I'll check again.
So I guess i'll remove the bolts from C, drop that part of the shaft and pull it away from B to disengage and lube? The diagram says "Yokes must be parallel", does it have anything to do with separating the slip yoke?

Thx

 

You are on the right track if you are sure your warranty is off. Yes, good way is to remove the drive shaft from the differential (around C). I think some people just loosen the center bearing, but IMHO loosening the back of the drive shaft is a little easier. Mark the orientation to keep everything exactly the same. Then you have to loosen the boot, and pull the rear portion of the drive shaft off for cleaning and lubing. Do a search to choose a good grease. I think I saw Glidecote recommended somewhere. And mark everything when you take it apart, so you can put it together the exact same way. I am sure I have seem some mini-writeups on greasing the slip yokes, will see if I can find them. Keep in mind that if this works, you will probably have to do this periodically. I think some people do it once a year, others with every oil change. One of the reason why I want to pursue the TSB route first.

Ignore the "yokes must be parallel" comment - yoke orientation and angles among other things are very important for drive shaft performance and durability, but you are not modifying anything in the geometry. Just make sure that everything goes together exactly the way it comes apart, so mark everything on the driveshaft and on the differential flange.

If you try it, would be interested how it works out. I hope my clunk comes back soon...so that I can either get the TSB done, or finally get on with cleaning and lubing the slip yoke myself. Good luck!

 

Looked at it again, there is not thing between B and C, just plain shaft. The pics show the rear and the front half of the shaft.

 

Ah....my bad... yes, your slip yoke is actually at the transmission side. Between the transmission and the U joint. I thought the prerunners are all the same now. Anyway, same concepts apply though and could still be the same issue. But instead of dropping the drive shaft in the back, you could try to loosen the center bearing and see if that gives you enough slack to pull the drive shaft out of the yoke at the transmission end for cleaning and greasing. I am not familiar with this though, so not sure if you get enough slack. Worst case you have to undo both the bolts at the rear diff and the center bearing, and then the whole drive shaft should slip backwards out of the slip yoke at the transmission.

I think this is what your driveshaft would look like: https://www.tacomaworld.com/threads/fs-driveshaft-complete-2005-13-prerunner-d-cab-short-box.359992/

The short stub is the slip yoke that slides on the transmission output shaft. You can try to clean and grease both the slip yoke and the transmission output shaft. Remember to mark everything.

And....wow....I can't believe how clean your truck is....

 

Lol....like I mentioned above it had been used by my kid just back and forth home to school and they did not bother to tell me any problem until warranty expired. This problem and the ac fan making noise which I had to fix myself.

Thx for the link. How did you find these, lol...anyway, I am going vacation soon plus having a little injury on my wrist but i'll post to let you know if I decide to go at it. Thx four your help again.

 

Ok, so I decided to look at the rear brakes for 2 reasons: squeals and I read somewhere here someone mentioned to check to make sure the rear brakes work properly to prevent energy build up in the spring leafs thus causing axle wrap. This makes sense too me. The car has 30k miles.

The rear brakes was messy as expected and the front shoes showed more wear than the rears, also as expected ( think it's normal for leading shoes to do more work). I rarely worked on drum brakes except to adjust the parking brake on my Odyssey and the adjusting hole was on the drum. So I assumed the same with the Tacoma and tried to adjust from the tiny hole on the drum. I was cursing at Toyota while trying to turn the star wheel. Later after I was done, I searched and realized the adjusting hole was in the back, on the back plate. I'll have to do this again to make sure the shoes are as close to the drum as possible.

2- After the brakes, I decided to pull the slip yoke. I was nervous because the shaft looked heavy plus it was getting late. I removed the mid-support bracket, which was not as tight as expected, and was able to pull out the yoke easily (I also marked both sides to make sure it go back the same way). First thing I saw was oil (transmission?) leaked out but not much. I didn't see any grease on the slip yoke nor on the trans side but they both were not dry either because of the oil. I didn't want to add any grease worrying it might get into the transmission and cause damage? I just put everything back and tightened the mid-support bracket a little more.

It's only been a few days but so far no clunks or very minimum, even when tried to push it by braking late to build up energy in the rear axle=axel wrap. I somehow feel it will come back eventually but will see. But for now, I am confused as why it's not doing it.

1- Can it be because my rear brakes are working better now and prevent energy build-up in the back? If this is the reason then the slip yoke is not the cause.
2- Was the oil supposed to be there, on the yoke, and has been there to work as lubrication? Or the leak of trans oil accidentally dropped on and lubed the slip yoke and now no more binding? Anyone?

I'll post to update if something changes.

thx

Edit: Readjusted my rear brakes again with the wheels on. It's still a pia to adjust because you can't see what you are doing. There is no room for your head to stick in there to look. The slot to for adjustment is pretty big and it became much better once I found where the star wheel located. What a difference !!! I can feel the resistance of the brake pedal much earlier now when coming to a stop. And parking brake can just be pushed just 2/3 of the way to hold the car on the hill tightly. I don't think it was this good even when I first bought the car brand new. I did as someone suggested on here: press parking pedal down just enough (may be 1/3 of the way) so that you have to use some force to turn the wheels. Then adjust until you can't move the wheels, or having to use both hands with good amount of force to move them. Release the parking brake and spin the wheels to make sure they move freely. The method really works. This also tells me that self-adjust doesn't work at all.

 

Glad your clunk is (almost) gone. Interesting on the rear brakes. Really don't know if it's related, but I can see how a lot of brake dust could potentially contribute to axle wrap.
On your question on the transmission oil: the oil you see there is basically small leakage from the output shaft. It's not necessarily designed to leak, but over time a small amount of leakage is ok. It's not designed to leak to lubricate your splines though. I would monitor it and if you start seeing drips on the floor, I would change the output seal. Doesn't look like a big leak from your photo, though. And I would add a little bit of grease to the slip yoke.

I finally spent some time on mine. Cleaned and greased the splines, which made a big difference, but did not fully fix the clunk. Re-torqued the U-bolts and clunk is gone - at least for now. Like you, I also expect this to come back.

 

Not sure if cleaning off the dust help much but adusting really helps, the shoes are much closer to the drums now but not enough to cause friction. Now when i brake, friction applied to both front and rear at the same time, no pushing from the rear (=energy build-up)like before. At least that's how i think it works but not so sure. I'll monitor to see if the clunk gets worse as the rear brakes getting close to the time of nedding adjustment again.