Stop/Start Clunk SOLVED - Trans Mount

I've had the infamous clunk going on for almost a year and it was getting worse. Some background: I have a 2010 4WD V6 OR A/T. The leaf springs are OEM 4-leafs and are about 2 years old. I have no suspension modifications or oversized tires. I wrote off axle-wrap due to the newer springs but did verify that the U-bolts were torqued to specs. I shoot grease in the spider joints every oil change on the drive-line. They are tight with no play at all.

I knew my carrier bearing had too much play so I replaced that and also took apart and re-greased the slip yoke. It was marginally better but after week I was back to the clunkage just as bad.

I next got a crowbar and saw that there was some play in the transmission mount. I didn't know how much is acceptable but thought what the heck and replaced it. I've put about 100 miles on the new mount and so much is better. No clucking at start/stop. I always thought a slight clunk was normal when going over the 2 inch lip entering my garage. That has stopped. I would baby the brakes coming to a stop and would coast before lightly hitting the gas on start up. Both would have a little knocking sensation. That has completely gone away.

The process of replacing the mount is easy but does take some work. I don't like the idea of horsing the transmission up high enough to clear the mounting knob on the cross member so I removed the crossmember. Also I'm not strong enough nor is there enough room to get a breakerbar on the top mount bolts. Removing the crossmember took some effort but can be done with a crowbar getting it out and a second floor jack to push it back in. I wish I had made a video but I was pressed for time (See explaination why below). Here's how to do it.

1) Remove the bolt on the drivers side body support bar attached to the crossmember.
2) Remove the 2 bolts on the heatshield. Do the ones attached to the crossmember to help make clearance so it won't hit the exhaust pipe.
3) Remove the 4 small bolts up through the crossmember to the transmission mount
4) Using a 2x4 wide enough to span the transmission pan, lift up on the transmission until the mount barely lifts off the of crossmember.
5) Now the fun, give the 4 nuts on the crossmember some penetrating oil. Horse those nuts off the bolts. I used on impact wrench hammering lightly until it broke free. There is a coating on the bolts so it takes effort to spin them off. Slide the crossmember bolts out.
6) Using a crowbar, pry the crossmember out. The frame has "wings" that squeeze the crossmember. It will come out. I then wire brushed both the frame and crossmember contact points. There was some rust so I wiped a little anti-seize on both sides. This helped with reinstallation.
7) Now I can get enough leverage to remove the 4 top bolts on the mount.
8) Remove the mount.
9) Put in the new one and tighted bolts to 40lbs.
10) Horse the crossmember back into position using a crowbar and a second floor jack to push it up. It will go.
11) Slide in the 4 crossmember bolts and tighten them to 30lbs.
12) Drop the transmission back down so the bottom of the mount rest on the crossmember.
13) Put in the 4 small bolts on the bottom of the mount up through the crossmember. Tighten these to a light 14lbs (168 in/lbs).
14) Put the heatshield and body support bar back on. Maybe grease the front propeller shaft first since you have it off.
15) Clean up and take it for a spin.

DO NOT USE A AUTOZONE DURALAST REPLACEMENT MOUNT. I was so mad I did this twice because the Autozone mount doesn't fit. The cheap Chinese version has a straight brackets. The genuine Toyota has these little jog-outs and fits perfectly. The Autozone one I bought online looked like the previous owner tryed beating it into submission and then gave up. Instead of throwing it away, Autozone just put it back on the shelf for the next fool (me) to buy. This time I put a big note in the box saying it won't fit. Autozone was $62. Dealer was $115. BUY A GENUINE TOYOTA MOUNT. Your time is valuable. I ended spending 3 hours taking it out, trying the get the AZ one in, and putting it all back together with the old mount. My wife was at work so no spare vehicle around. I had to drive my truck to the dealer and then Autozone to take the other one back. Like doing drum brakes - the first side is one hour and the second side in 15 minutes. The next morning I put in the OEM one in 1 hour.

These pictures of the Autozone mount next to the old mount shows how far off the specs are and why it didn't fit. You can see the old mount has these little jogs to top sides where the AZ one is straight. The OEM mounts both have white plugs. You can see how much more of a gap there is on the old mount when relaxed as compared to the new one.

 

Glad to see this helped. How many miles are on your truck? Where do you live?

 

Thanks for the write-up. I've been contemplating doing this to my wife's truck as I've tried everything else to get right of clunks and the all too common 15-20mph vibration. How much play were you seeing with the crow bar?

 

Great info! Thanks for posting!

 

Just be careful jacking up on the pan, I crushed a pan like that.

 

I got 129,000 miles. I live in Utah.

 

I would say 1/2 inch. The thing rest exactly in the same position as the old one but I think it has a lot more support and doesn't compress as easily.

 

I agree. That's why I used a 2x4 and made sure it was under the sides and back to help support it. I barely raised it up just enough (like 1/16") off the crossmember. I've seen post where people jack it up high enough to clear the white allignment plug. That's like 1.5 inches. I think that's too much pressure on the pan.

 

What did the old mount look like that was worn out? I've been chasing a start off clunk I'm certain isn't my drive shaft and there's a good chance it's this. It's not a noise but rather a feeling. It's as I apply power. It almost felt like it was when the truck loads back as the wheels start to push.

 

I've got what sounds like an identical clunk, right when I start off and occasionally when I shift into 2nd (6-speed manual).
Drive shaft seems solid, plus there seems to be a recall out for certain trucks (2005-11 4x4 AC and QD) if there is an issue. Maybe it's the trans mount?

 

The top one in pictures 3 and 4 are the old OEM vs new OEM. The one with the black alignment plug is the junk Autozone one. That "feeling" you mention is also what I was experiencing also.

 

Has anyone in here has issues with clunking/vibrations in only 1st gear and reverse at low speeds (more often it happens in reverse). Im guessing it's the trans mount after 250k.. ordered a new one, hope it fixes the issue

 

Hmmm, I have a 2010 A/T with 142,000 miles and I have noticed this "clunk" sound

 

I have what feels to be a settling feeing when coming to a complete stop and when taking off unless really light on the throttle it feels like a clunk but no sound just a feeling been to the dealer twice and they say they don’t feel it. Is this similar to what you guys are feeling?

 

What year? Sounds like axle wrap. 2 recalls depending on the year may apply. Recall on u-joints and recall on leaf springs.

Depends on how long you are going to own the truck....


If recalls don't apply, you can try temp fixes like replace the carrier bearing, u-joints and/or add shims. Do the work yourself, $400 . IF, Big IF, it fixes the issue, within 5 years, your doing it again. If lifted, sooner

Or fix for good, one piece driveshaft, custom leafs. Worst case, I mean worst case, total custom, $2000. Done for good!

 

Mine is a 2005 with a little over 200k. I plan on keeping it as long as I can because the frame was replaced in 2014 and it barley has any rust. The motor still seems reliable but not sure for how much longer but runs good. I plan on doing some light changes like a small lift and some cosmetic changes if I can get some of these other bugs worked out.

 

Input requested- is this too much play?