Hey gang - 2005 4Runner SR5. All Stock. 175K Really annoying and intermittent issue that I can't figure out.

Earlier in the year I was experiencing a slight but noticeable shudder when accelerating at slow speeds around the 20 - 30 MPH mark. It was only on acceleration. Not coasting or braking. I remember experiencing something similar years ago, and the suggestion was to drain and refill the transmission oil. 3 years ago that solved the problem. Shudder disappeared. So thinking it was a similar issue, I drained it again (over the course of 3 months, 1.5 quarts at a time until completely recycled with new Trans fluid; Toyota genuine oil).

As of today, the shudder I felt when I first started this months ago has gone away. But a NEW issue has surfaced and I don't know if it's related.

When coming to hard stop from a generally fast speed (not burning rubber or excessive braking; just braking a little harder than normal to slow the car down relatively quickly), the car will JOLT within a few seconds after stopping. Now this doesn't always happen. and I'd say 80% of the time it's fine. But every so often at the exact moment when I stop, within 2-4 seconds AFTER stopping from a relatively hard brake, I feel a jolt...like it's finishing the last downshift back to 1st gear but in a very hard way. Sometimes it's strong enough to literally push the car forward an inch or two.

I can't think of any other way to describe what's happening. I don't know if it's Transmission related or not. But it certainly feels like something connected to the drivetrain is not keeping up with the vehicle's momentum.

Any thoughts would be appreciated!

Try greasing the zerks on your driveshaft.

@john123drury mine does the same thing and it gets worse when I have my A/C on. Make sure your driveshafts are greased front and rear.

Specifically you want to grease the zerks on the slip yokes of both drive shafts. The u-jointa themselves only get a couple pumps, but the slip yokes can get as much as 25 pumps of grease. Commonly, you pump until you see slight movement in the yoke. Common issue with these trucks

Are you sure? I thought I recalled reading the opposite across multiple threads. That the slip yokes ("sliders") only get MAYBE 3-5 pumps of grease, and that the ujoints ("spiders") get multiple pumps until the grease starts coming out. That putting too much into the yokes can cause them to lock up. Am I misunderstanding?

I had same isue about 4 years ago. Their right, My yokes took a dozen or so zerks and u-joints maybe 3 zerks tops. No thumps/bumps since then.

+1 for greasing those zerk fittings. I had mine done when I had some other work done on my 4r and no more bump!

It can depend on how often its been greased before. You want to pump until you just barely see the seal/yoke move, then stop as its full. You don't want to over fill as you'll blow the seal out and that's a huge pain. My 2009, with 110K at the time just after buying had likely never been greased before and was clunking pretty bad every time you'd stop and accelerate. Front took almost 70 pumps before I saw any movement, rear was closer to 100. Yokes are nice and tight now, and it just needs a pump or two every 10k to move. YMMV

Ok I greased the zerks but unfortunately the problem is still there. I'm going to put up another post with the new/different symptoms today

what about the method that you pump the yokes untill the "pumping" get firmer.

i have a 2006 4wd with 192k and i did that today and it took about 10 pumps untill i noticed that the pumping got a firmer, so i stopped. i dont think anyone pumped grease in for at least 50k

For those who may experience something similar down the road, I believe I have figured out the issue. Trans fluid was too low. That is why I would experience the symptoms more when I would come to a harsh stop or turn. Because whatever limited fluid was in the case wasn't enough to keep the hydraulic pressure when gravity pulled it to one side or another. Added more fluid and triple-checked the levels. Seems to be running much better now.

I'm wondering if this would solve my issue as well, my symptoms are the same except once in awhile after the jolt I experience a weird loss of throttle, my rpms can go up at a normal rate as i push the gas down, but the car accelerates very slowly, and I have to turn it off and on to fix the issue. Did you experience anything similar?

Marking this for further review...I am having the same issue!

Did you try to grease the driveline zerks?
For the bump feel.

Not sure with the throttle loss, had it happen to me a few weeks back.
Been looking at that Sonex Zip Kit. For the tranmission.

Greasing the slip-yokes gets so many different opinions across different forums and even within them for some reason. There seems to be no real consensus on how much grease to pump into the slip yokes. Some say pump till you see movement (I've done this) others say to only pump around 5 pumps to avoid locking them up and creating damage to the transfer case/rear diffs upon hitting bumps etc.