Water pump wobble and question for Hart Rod and Br3w 6L80E

[Houston Ben]

Hey all,
2011 5.3/6L80 combo. While driving today I noticed a slight vibration under normal driving. It appears about half way through the rev range when doing some easy driving. It almost feels like a break draggin but goes away. This happens in every gear and when cruising I can feel it when slight pedal input is applied, when I let off the pedal it goes away. I checked fluid and it is good, any ideas???

Also, while looking under the hood for this I noticed my water pump and balancer wobble a little, is this normal??

https://www.youtube.com/watch?v=zNye...ature=youtu.be

[BR3W CITY]

The pulley looks a little wonky, like maybe the pump was dropped at one point or something?

How many miles have you put on the swap Ben? What your describing is sometimes actually caused by cam surge, but that is unlikely to be an "overnight" problem. Its something that would happen after a tune or change in equipment on the existing tune.

[Houston Ben]

Hi Br3w, thanks for responding. I probably have 2-3k miles on the swap, odometer not currently working. I guess I might have to bite the bullet and buy hptuners and laptop, not that I know how to use it. As far as the water pump, idk, could have been by the yard it came from. It has t created a problem, just didn't know if it was part of the current problem.

[Houston Ben]

Should I not be driving it?

[cableguy0]

Pull the belt and try to move the pulley by hand. If the pulley moves then the bearing in the pump is bad and the pump needs replaced. Water pumps wear out and should be replaced when you swap in the engine. Also make sure to replace the thermostat with one that matches the water pump.

[Houston Ben]

Thanks!

[Hart_Rod]

Do you have the DOD/AFM disabled in your tune?

[Houston Ben]

I have no idea Hart rod. I guess I'm going to have to buy HPtuners and see if I can figure anything out, never used it before. Should I be driving with this vibration??

[BR3W CITY]

Originally Posted by Houston Ben

I have no idea Hart rod. I guess I'm going to have to buy HPtuners and see if I can figure anything out, never used it before. Should I be driving with this vibration??

That depends, did you check the above-ideas on the water pump? If you can verify that the pump isn't gonna fall off or seize while your going down the road, then you aren't in any danger by doing so...it might be a good idea to keep an eye on the temp gauge just in case.

...but if there is a problem we haven't diagnosed yet, I don't want you to put serious miles on it an accellerate the wear process.

Who did your tune Ben? You should be able to ask them if afm was removed. While buying HPT is awesome, in this case we might be able to get the info from your tuner before going that far.

[Houston Ben]

Hi all,
I am going to check the pump tonight when I get home. Last time I drove it (Friday the 22) the temp stayed between 190-195 the whole time in this Houston heat. Sorry, I should have been clear on the second time I asked if it was ok to drive as I was speaking for the cam surge that time. I will ask my tuner to see what he did but out of curiosity, how bad is cam surge?

Also, sorry if I should know but I don't, what are DOD/AFM?

Thanks for the replies and I will update when I get home.

[boostedc10]

DOD is displacement on demand and AFM is active fuel management. Are you asking how bad is it for the motor?

Typically cam surge wont damage anything. Is this a stock cam motor?

[BR3W CITY]

Cam surge is a driveability/performance issue, not really a "problem". Its more common the bigger the cam is, because the ecm wants to bounce back and forth shooting for stoich.

If your going down the road at 35mph giving it 10% throttle, then all of a sudden it feels like you need to give it 20% throttle to go the same 35mph...thats cam surge.

If your going 40mph at 20% throttle then randomely it feels like you only need to give it 15% to go the same speed...thats the OTHER side of that cam surge.

[Houston Ben]

Ah, got ya, Thanks Br3w!!

Thanks all who have responded, it is much appreciated!

[Houston Ben]

Thanks Boosted!

[boostedc10]

Np Ben. Is your motor stock cammed? Did you take it and have it tuned or just send in an ecm somewhere to have the normal stuff removed?

[Houston Ben]

Motor is stock cam and I took it to a person to have stuff removed and tuned. He just got back with me and stated they always turn off the AFM but the dod lifters are weak and tend to fail....I have no idea what that means!! lol.

Thanks again guys!

[Houston Ben]

Ok, he stated DOD is NOT turned off. Said he could turn it off electronicly but I would need to buy a bunch of parts to turn it off mechanically as well.

[Hart_Rod]

Originally Posted by Houston Ben

Ok, he stated DOD is NOT turned off. Said he could turn it off electronicly but I would need to buy a bunch of parts to turn it off mechanically as well.

I bet that's the surge you feel..

[Houston Ben]

Just checked, water pump and balancer do not move.

[Houston Ben]

Just took it for a test drive, seems more noticeable when turning. It still there how ben slowly driving through the gears or when at speed and keeping steady to slight more pressure to pedal...

[Houston Ben]

Hart Rod, do I really have to buy some part to turn it off as well?

[Hart_Rod]

Originally Posted by Houston Ben

Hart Rod, do I really have to buy some part to turn it off as well?

You can turn the AFM off within the tune, just a click of a button. If you were going to change the cam to one with a high lift (.600+) and install dual valve springs, then I would recommend you mechanically delete the AFM, as AFM lifters are a weak point and don't like high lift or RPMs. With stock motor, you should be good with just turning it off in the tune, JMHO.

[Houston Ben]

Ok, I figured out the vibrations problem but still stuck with a problem.

I took off the DD a/c bracket and put on the old belt tensioner with serpentine belt and bingo, vibration was gone

Problem now is, why does it vibrate with the dd and compressor attached? Anyone have any experience with the DD ac mount on a truck engine??

[Houston Ben]

Anyone have any ideas? Ac compressor is not hooked up yes so it is just acting like a pully for now.

[BR3W CITY]

Does the pulley on the DD bracket spin ok when off the car? If it had a bearing go out, it would chatter and vibrate a ton.