Driveline "bump" after a stop

[Husker Z]

I've seen it mentioned before, but couldn't find where there was a solution to it. When I make a "somewhat" quick stop at a stoplight, when I let off the brake, I feel a "bump" in the driveline, almost feels like someone rear ended me to be honest. No other symptoms or anything and it's not 100% of the time, but it will do it most of the time after a firm stop.

Thanks in advance. I tried a search, but I wasn't sure what to search for and nothing was really coming back with the info I was looking for.

Thanks!

 

[Doozi]

That's your rear drive-shaft... sounds like you need to lube it. My "thump" is starting to come back, so I'll be lubing mine this weekend. It's VERY common!

~Doozi

 

[sonerick]

Yep, mine thumped too for a bit. Lubing the driveline seems to keep it at bay for about 10000 miles or so.

http://www.toyota-4runner.org/maintenance/28414-07-v8-4x4-zerk-fitting-pics.html

I used Mobil1 synthetic on all the fittings, seems to work well. It took lotsa pumping before I noticed the front and rear slip yokes expand... hope you've been doing some forearm workouts in your off time!

 

[Husker Z]

Awesome, thanks for that link too, that helps.

Oh man, I'm married, so you know my forearm is pretty strong!

 

[Nuke]

+1 on very common. I had it on my 3rd gen, also. My understanding is that it also has to do with the suspension "loading up" and when you release the brakes, some of that energy is released and we feel a thump. I still automatically look in the rearview, though.

 

[Husker Z]

+1 on very common. I had it on my 3rd gen, also. My understanding is that it also has to do with the suspension "loading up" and when you release the brakes, some of that energy is released and we feel a thump. I still automatically look in the rearview, though.

Yeah, it's a strange feeling, for sure.

So, just like when you grease anything else, just pump it until you see it oozing a bit, right? I normally like to use Amsoil grease, but I don't have any on hand right now, so I'll just grab some Mobil 1.

 

[sonerick]

So, just like when you grease anything else, just pump it until you see it oozing a bit, right? I normally like to use Amsoil grease, but I don't have any on hand right now, so I'll just grab some Mobil 1.

For the 4 u-joint fittings, yes. Pump until the old black goop starts to ooze. Usually 5 or so pumps of a normal size grease gun will do.

For the 2 zerks on the slip yokes entering the tcase (1 front and 1 rear), pump until you begin to see expansion in the slip yoke. Using a normal size gun, this took me about 50 pumps.

The first time I did it, the zerks were so crusted up that I had to use a nail to pop the ball bearing inside loose a little bit.

 

[MICA4R]

use lithium with moly on the slip joints = 100% problem solved.

use mobil 1 on the other 4 u-joint zerks.

 

[eliask08]

Over-greased yoke?

Wow, so that is whats causing the bump. Two months ago, I honestly thought that the dorito's truck behind me actually rear-ended me.

So, I just came out from a sub-zero garage, after greasing only three zerks. There are no six zerks as others have shown. I slowly rotated the wheels, which spun the shaft, and only found one on the rear U, one on the front U, and one on the front slip yoke. Could it be that my 05 4WD (Canadian model) does not have the remaining three? The haynes manual I have also indicated only three.

Secondly, I pumped the yoke slowly, but did not see it expand. By the time I realized nothing was moving, the grease gun was incredibly stiff. I am worried that now I may have over-greased the damn thing. Should I be worried?

 

[netwon]

Wow, so that is whats causing the bump. Two months ago, I honestly thought that the dorito's truck behind me actually rear-ended me.

So, I just came out from a sub-zero garage, after greasing only three zerks. There are no six zerks as others have shown. I slowly rotated the wheels, which spun the shaft, and only found one on the rear U, one on the front U, and one on the front slip yoke. Could it be that my 05 4WD (Canadian model) does not have the remaining three? The haynes manual I have also indicated only three.

Secondly, I pumped the yoke slowly, but did not see it expand. By the time I realized nothing was moving, the grease gun was incredibly stiff. I am worried that now I may have over-greased the damn thing. Should I be worried?

I have a Canadian 4runner and I can tell you there there are 6 as others have posted. Front shaft has one on each u-joint and 1 for slip (3). Rear has the same. The front shaft rear most u-joint is a b***h to get to (grease gun needle fitting helps), but having the truck on stands helps if you have a V8 as you have no way to turn the front shaft otherwise. I tried driving forward and backward to line up fittings but way to bothersome (no neutral). I don't think you can really "over" grease *BUT* if you do you'll have a huge mess as the excess grease will tend to fly off the joints and collect dust and grim under the truck and on the joints. I fill the joints until I hear a slight snapping sound of fresh grease coming out of the bearing caps. Hope that helps.

 

[CNJ Runner]

is this covered under warranty?

 

[M1911]

is this covered under warranty?

Greasing the driveshaft is not warranty repair, it is standard maintenance. Grease the driveshaft every time you change the oil. It's not a big deal, and no shop is going to charge you more than $30 to do it.

 

[truckmike26]

Wow, so that is whats causing the bump. Two months ago, I honestly thought that the dorito's truck behind me actually rear-ended me.

So, I just came out from a sub-zero garage, after greasing only three zerks. There are no six zerks as others have shown. I slowly rotated the wheels, which spun the shaft, and only found one on the rear U, one on the front U, and one on the front slip yoke. Could it be that my 05 4WD (Canadian model) does not have the remaining three? The haynes manual I have also indicated only three.

Secondly, I pumped the yoke slowly, but did not see it expand. By the time I realized nothing was moving, the grease gun was incredibly stiff. I am worried that now I may have over-greased the damn thing. Should I be worried?

I wouldn't be worried. I pumped and pumped mine until the slip yoke just started to expand and the driveline bumping problem disappeared like magic. But, as was stated above, I feel a slight bump returning, which means it might time for another session with the grease gun although I'm sure it won't need nearly as much as it did initially (untouched from the factory).

 

[crooper]

Oh this is so helpful. I've been greasing the Zerks on my 08 and successfully getting the 4 to push out the old grease, but the other 2 I kept pumping and nothing really happened so I stopped cuz I didn't want to break anything. Next time I'll make sure to fill it full.

 

[message]

Greasing the slip yoke, by GORDO, as noted here:http://www.toyota-4runner.org/probl...-aka-driveshaft-thump-bump-45.html#post533780

If you are greasing the slip yoke for the first time it's going to take a LOT of grease. Make sure you pump grease until you hear a hiss which is the trapped air coming out the seal. Keep pumping until you see grease come out. You need to do this since only greasing the slip yoke until it expands does not lube the slip yoke, it only puts pressure on it.
Once there's grease coming through the seal make sure you jump a few times on the back bumper. This will take the pressure off the slip yoke and push more grease through. Others remove the zerk to release the pressure, though I find jumping on the bumper easier. Last cleanup all the grease so you don't coat the underside.

Also if you are having trouble accessing all the zerks jack up the 4runner so that both wheels are off the ground on one side(that's if you have a v8 with FT4WD). Then you can free spin one of the wheels and the other will move as well so you can access all the zerks.
NOTE: You can do this with the 4runner in Park and with the other 2 wheels chocked, which you should be doing for safety anyways.

 

[M1911]

Also is you are having trouble accessing all the zerks jack up the 4runner so that both wheels are off the ground on one side(that's if you have a v8 with FT4WD). Then you can free spin one of the wheels and the other will move as well so you can access all the zerks.
NOTE: You can do this with the 4runner in Park and with the other 2 wheels chocked, which you should be doing for safety anyways.

Put it on jack stands if you are going to do this. Don't get under the truck if it is just being held up by a jack.

 

[message]

I specified jacking up the 4runner only to free spin the wheels, not to crawl under it. I figured that was a given, but yes jack stands should be ALWAYS be used if you are going under a vehicle. NEVER trust only the jack.
It is a tight fit, but you can slide underneath without jacking up the 4runner if you have to. So all you have worry about then it a tire going flat

Put it on jack stands if you are going to do this. Don't get under the truck if it is just being held up by a jack.