05 Tacoma Hard Thump on acceleration and decceleration

Hello Tacoma World,

New/2nd owner of an 2005 Tacoma Double Cab 4.0L Base with Auto trans. 141,000 miles with a decent service history mostly preventitive. However no records on any Transmission services. I noticed a hard thump coming from under dash when i would press hard on accelerator and when i would let off the accelerator abruptly it would thump again.

Another issue i noticed was first time i drove in morning when i would back out it would clink/clunk with the application of brakes or just when i would shift from park to reverse i would notice an audible clink/clunk. I would notice again when braking going forward the first time i drove and then it kind of went away. I felt these were entirely two different issues.

I tried to read every forum i could read to try to see what others had found. My Tacoma has Spicer drivelines with zerk fittings. 3 for the rear drive line and 2 for the front. It also has 2 zerks on each sway bar link. I greased all 9 zerks and they all took at least 5 pumps a piece. This didn't fix the hard thump or the clink.

I jacked up the truck removed tires from the front wheels and took brake caliper pins out and wired brushed them and greased with brake grease, and put back on. This changed the audible note coming from the clink i had when braking it made it less noticeable and made in more of a soft clunk/clink.

I decided to drain transmission oil, i got about 3.2 quarts out of the transmission, I won't comment of condition of the oil because i don't know exactly what I'm looking for. But i decided to overfill the oil by about 1/2 quart. I got transmission up to about 100 degrees and took the check level plug out and no fluid came out. So i added about .7qt of fluid before i noticed a trickle coming out. I did this with the truck running, by the time the fluid started to come out the temp of trans was about 105 degrees.

After filling the transmission with approximately 1.2 quarts more than i took out it doesn't make the same thump I was getting its almost gone after servicing the transmission with the amount of fluid i think it should have.

Any thoughts/opionions on having a low quantity of Trans fluid and if this would have any bearing on the hard thump i felt under my dash?

Thanks for any help, and I wanted to share my story to maybe help anyone else with similar symptoms.

 

check carrier bearing?

This one (my old one) was obviously bad, but its part of your driveline. I think I read somewhere that it should have 1/2" of play?

https://www.youtube.com/watch?v=jzabcym5Lek

 

I would check the integrity of the transmission mount.

 

Based on what you posted above, while all that additional maintenance is good, it sounds like axle wrap. On acceleration and braking, your leaf springs are twisting and unloading. You might also want to check your hanger bolts for proper torque. IIRC they should be about 81 ft lbs (please verify). Torque them in an 'X' pattern. Also, take a peek at your front leaf spring and rear shackle bolts/bushings. They could be on the way out.

-J

Edit: upon re-reading, it sounds like there could be more than one issue going on. Difficult to armchair diagnose but I would also peek at your front suspension components. Paying close attention to your bushings. Check for metal on metal contact, especially throughout the movement range.

 

You either have axle wrap, carrier bearing damage (this one is more likely) or a bad trans mount.

At 141K miles, they are probably all shot to hell. The trans mount is probably okay though.

 

Thanks for the reply's team, This seems like a pretty active forum.

I did check the carrier bearing it was in really good shape it has some flex all around but 1/2in is about what it seems. I checked the front 2 engine mounts visually and with a pry bar and by doing the brake check in drive and then reverse to switch the direction of torque. I didn't notice any play that seemed excessive. On the rear engine/trans mount it looks fairly new i did put a pry bar under it and tried to apply different angles of pressure and it seems like it is in good shape the rubber bushing part seems like there is no rips or disbandment. But I'm not an auto mechanic so my experience with these types of application is limited lol..

Is there a better way to check these mounts?

It does have a new frame and brake lines and new u bolts and looks like new rear leaf springs.

 

Also, could be a sticking slip- joint on the drive shaft.

 

Half an inch of play on the carrier bearing is too much play and can allow vibrations and even thumps under the right circumstances. Take both sides of the shaft and push them up and bring them down and see how much play it has overall.

As of right now, it sounds like either you have a bad carrier or weak leaf springs.

 

I was reading about those splines in the yoke that may need greased to tighten the tolerances, i may drop drive line pull that out thanks.

I don't notice the thump when braking. I only notice when trans downshifts hard and grabs a gear and then when i let off the accelerator quick it will thump again at almost the same intensity. But after I refilled transmission with proper amount I can't really replicate the hard thump again. Before i could hear it and it would jolt the entire cab mainly under the dash. That thump was a tad alerting.

When i called a local Toyota service advisor they said that it is more than likely in the torque convertor and that it was common and to just be easier on the throttle and I wouldn't notice the thump. Which i agree it is controllable by managing the accelerator gently or modestly. But he said its normal for all vehicles which I disagreed having owned multiple vehicles and never felt a thud or thump that violent and described as normal.

 

I will try to post a video of the play in the Carrier bearing. I guess i could do it through my phone?

 

You can, but a properly built vehicle (which these are) will not exhibit torque converter shudder. That is a myth, at least on these vehicles. If it is controllable through the pedal that is 100% without a doubt the carrier bearing. Based on the amount of play you mentioned, that bushing holding the bearing together is now garbage. It has always been to be honest.

I have two recommendations for you, go get a flush and get rid of that Toyota WS transmission fluid and put in Valvoline Maxx Life ATF. All 11 quarts that transmission takes, and then go get your carrier bearing replaced with either a direct fit unit built by Spicer, or put in some work and install one with a yellow Polyurethane bushing built by Inland Empire Driveline Service.

Here are two links which should give you plenty to read on.

https://www.tacomaworld.com/threads/carrier-bearing…-alternatives-and-solutions.419706/

https://www.tacomaworld.com/threads...uy-iedls-polyurethane-carrier-bearing.421410/

 

The website won’t let me upload the video from my iPhone is there a way I need to reformat? It saying it’s .mov I think

 

I did fill the trans pan with max life atf after my first drain. I was going to do a drain and fill about every week for about a month. Until it comes out clean.

 

YouTube is your best bet.

 

Yep. It's like I thought, WAY too much play. It's fried. Replace it now, you know your options.

 

Ok awesome, thank you for commenting. After going back and reviewing video it does seem a bit more than I originally thought.

 

How about the motor mounts? Don't some year Tacomas have motor mount issues? Open hood, have somebody put it in reverse with the ebrake on and rev the engine. See how high the motor jumps.

 

There a slight vibration I feel through steering wheel as RPMs increase. I didn’t think to mention that but I seen 12rd commented that the carrier bearing could be a the instigator of that issue as well.

I did check Engine mounts those seem ok. But I may need to upload a video of those and get some feedback to be safe.

 

Here is a picture of the truck