Powertrain vibration (drop kit) HELP!!!

[2010SLVRBULIT]

just put the original springs on, see if the problem is still there. At least you can take it back to dealer for a free fix.

[JusticePete]

Originally Posted by 2010SLVRBULIT

just put the original springs on, see if the problem is still there. At least you can take it back to dealer for a free fix.

There is no guarantee of a free fix with the OE coils installed and that creates an issue for Luis. $800 is the bill to take off and put back on the lowering coils. If GM doesn't warranty his repair, then Louis is out $800 plus the cost to repair the vibration.

Luis has posted his car was fine before the last pass on the track. Something went wrong on that pass and the probability it is his lowering coils is some where between slim and none. His chances of warranty are not much better and would depend on there being a defective part.

Just my opinions.

[Info@PeddersUSA.com]

Originally Posted by Ltdodge

ever since camarofest after i ran the last time down the track, i had some wheel hop and after that the car seemed to be vibrating under load in the rear (3rs, 4th and 5th gear) and it projects through the transmission,shifter and the car shakes, well I took car to dealer since it seems to be vibrating more every day and they told me that part of the problem is since i have a suspension drop (pfadt springs) the axles are vibrating due to a different angle, the called GM and they said since i have a drop kit they cant do anything about it...I think this is GM BS covering their butts, the car was perfect before the fest, so i don't think it can be the springs

this car is vibrating like hell...help me!!! what can I do?

the dealer told me to install the stock springs back and see if it goes away and if it does not to bring it back, but this will cost me over $800 to install twice. they also recommended to install high performance axles to eliminate this???

do you have anybody know anyone in the central Florida region that can check my axles and see if they are bent or so?

Luis

Coming from a GM dealership background, they are covering their butts. They are probably not familiar with aftermarket components to look at it in a more rational way. But they just want to eliminate variables. You are fortunate they will assist you. The cost of the axles or driveshafts would more than likely exceed the $800. So I would do as they asked and get the springs back to OE. After they find out what the issue is and fix it, then you should chat with us on a resolution to assist you in more control of your back end. But we first need some info:
1. What rear hp are you running
2,. What wheels and tires are you running
3. How often are you going to drag race
4. What potential engine mods are you going to do if any.

With this data, we can assist you with supplemental components to reduce unwanted movement, which will help with wheel hop, which if something is damaged, most likely occurred from this.

thanks
mike
dms

[Ltdodge]

Originally Posted by dms

Coming from a GM dealership background, they are covering their butts. They are probably not familiar with aftermarket components to look at it in a more rational way. But they just want to eliminate variables. You are fortunate they will assist you. The cost of the axles or driveshafts would more than likely exceed the $800. So I would do as they asked and get the springs back to OE. After they find out what the issue is and fix it, then you should chat with us on a resolution to assist you in more control of your back end. But we first need some info:
1. What rear hp are you running
2,. What wheels and tires are you running
3. How often are you going to drag race
4. What potential engine mods are you going to do if any.

With this data, we can assist you with supplemental components to reduce unwanted movement, which will help with wheel hop, which if something is damaged, most likely occurred from this.

thanks
mike
dms

thanks for your help,
i never run, just ran at the camarofest that day to see what it has (I wish i never did it). at the time i was running the stock tires now i have 315 in the rear. i will probably never dragrace at the track ever ever ever again and for now i have the LT, exhaust and CAI, maybe future cam.

I just want my car to run correctly and not vibrating, hopefully Next level will find the culprit.

but i have a question, me any my buddy lifted the rear and put jackstands. we then started the car and put her in gear and looked at the axles, it seems like the axles at the differential was not spinning concentric but rather had a slight elliptical spin to them, this was at both axles, are they suppose to spin that way?

[Info@PeddersUSA.com]

Originally Posted by Ltdodge

thanks for your help,
i never run, just ran at the camarofest that day to see what it has (I wish i never did it). at the time i was running the stock tires now i have 315 in the rear. i will probably never dragrace at the track ever ever ever again and for now i have the LT, exhaust and CAI, maybe future cam.

I just want my car to run correctly and not vibrating, hopefully Next level will find the culprit.

but i have a question, me any my buddy lifted the rear and put jackstands. we then started the car and put her in gear and looked at the axles, it seems like the axles at the differential was not spinning concentric but rather had a slight elliptical spin to them, this was at both axles, are they suppose to spin that way?

I think what you are seeing with your axles is fairly normal and this nis why. When you have your Camaro in the air, the angles of the half shafts are too extreme, thus creating a potential bind, thus the movement. In retrospect, if you had say a 1/4 inch movement at speed, the vibration would be so serious, you could not drive it. A better way would be to support the lower control arms and get the angles back to normal range and recheck.

I do not think your drivetrain has anything to do with your drop springs. I would speculate however, if your drivetrain is vibrating, it is most likely the result relating to wheel hop. We have seen axles break running a program plus a CAI with 6 speeds. So after they have diagnosed your concern, we should look at this approach to support you and eliminate the variables that cause this wheel hop/excessive movement when playing.

If you are interested give me a budget and I will put something together for you.

thanks
mike
dms

[Bmble_B]

Tire/CV axle vibrations occur in the same frequency because they rotate together; about 13-18 cycles per second, slow in terms of vibration. Driveshaft/propeller shafts vibrate in the 60-80 cycle pe second range, somewhat faster. You have to determine the frequency of the vibration. A seasoned tech can tell the difference in a tire vibration and a driveline vibration and diagnose from there. GM had a frequncy meter years ago that you put in the vehicle to determine the range and then diagnose the component from there. Rotating assemblies are balanced pretty well today, not needing this device much today. Before changing your springs I would seek out a good front end shop that can diagnose vibration problems and give them a shot. From what you say it sounds like you twisted something and now it's out of balance. you can PM me if you want. I do this for a living. I think I can help.

[Ltdodge]

ok, took car to next level performance and this is what they kinda found out.... they put the car on the rollers to checkout out the system. driveshaft, axles, u joints all look good. what they did see was that the rear cradle bushings would flex under acceleration and there was a 1/4" gap between the washer and the rubber bushing when you accelerated under load, they told me that maybe the bushing was messed up or maybe the bolt elongated creating a gap when under load, they observed it on both sides fluctuating.

now, the stock bushing i believe has a center that is metal held by a rubber web. if the rubber (web) broke the metal portion goes up and down and does not do that the bushing is supposed to do....

what do you all think?

on another note I put down 398 hp and 389 torque after a long drive, massive heat soak and almost 102 degree heat index today with my mods. baseline at the same dyno was 352 hp and 358 torque.

[JusticePete]

Originally Posted by Ltdodge

ok, took car to next level performance and this is what they kinda found out.... they put the car on the rollers to checkout out the system. driveshaft, axles, u joints all look good. what they did see was that the rear cradle bushings would flex under acceleration and there was a 1/4" gap between the washer and the rubber bushing when you accelerated under load, they told me that maybe the bushing was messed up or maybe the bolt elongated creating a gap when under load, they observed it on both sides fluctuating.

now, the stock bushing i believe has a center that is metal held by a rubber web. if the rubber (web) broke the metal portion goes up and down and does not do that the bushing is supposed to do....

what do you all think?

on another note I put down 398 hp and 389 torque after a long drive, massive heat soak and almost 102 degree heat index today with my mods. baseline at the same dyno was 352 hp and 358 torque.

I am not aware of of any OE cradle bushes failing and would love to see them in person. The deflection they are seeing is what we would expect from the OE NVH bushes. Unless a bolt is loose I doubt that is the source of the vibration.

Did the shop that installed the springs ever drop the rear cradle?

Are the bolts tight?

[Info@PeddersUSA.com]

With the OE bushings at the rear subframe/cradle, there should be no gaps between the lower plate and the bushing. The lower plate is in fact a press fit into the center OE ferrule.

Now, the OE stuff will in fact move maybe 1/2 inches or so in all directions. I am questioning whether this is your issue or not.

To start, however, can you get us a picture to make sure we are all in sink with you? And as Pete mentioned, are the bolts tight?

thanks
mike
dms

[Ltdodge]

Originally Posted by dms

With the OE bushings at the rear subframe/cradle, there should be no gaps between the lower plate and the bushing. The lower plate is in fact a press fit into the center OE ferrule.

Now, the OE stuff will in fact move maybe 1/2 inches or so in all directions. I am questioning whether this is your issue or not.

To start, however, can you get us a picture to make sure we are all in sink with you? And as Pete mentioned, are the bolts tight?

thanks
mike
dms

here is a pic of the sub frame mount. does the angle of the plate look ok? you can see there is some gap...

[JusticePete]

I see what you are saying. Can you get a tech to try to tighten all four sub-frame bolts?

[J-Rod6410]

From my 20 plus years of experience, this sounds like a bad U-joint in the driveshaft. Of course, these cars don't have U-joints they have a flexible rubber mercedes benz type coupler Anyway, if there is a single bolt that is loose on that driveshaft it will vibrate. If there is a MISMATCHED bolt, nut or washer, it will vibrate. If a washer is missing for some reason, it will vibrate. You have on each side of the driveshaft 6 bolts in sets of three matching. All the bolts, washers, nuts must be properly tightened. All of the matching bolts must be installed in the same direction(for example: all bolt heads on one side and all nuts on the other side). I just fixed this problem on my car this weekend. I had a viration in the drivetrain and I found a loose bolt, probably because of previous wheelhop and racing. I tightened the bolt and problem solved. The springs will NEVER cause a vibration unless you drop the car 4 inches and slowly damage the axles, then it might lead to a viration. Have those bolts checked


Hope this helps, jrrod

[Info@PeddersUSA.com]

Originally Posted by jrrod6410

From my 20 plus years of experience, this sounds like a bad U-joint in the driveshaft. Of course, these cars don't have U-joints they have a flexible rubber mercedes benz type coupler Anyway, if there is a single bolt that is loose on that driveshaft it will vibrate. If there is a MISMATCHED bolt, nut or washer, it will vibrate. If a washer is missing for some reason, it will vibrate. You have on each side of the driveshaft 6 bolts in sets of three matching. All the bolts, washers, nuts must be properly tightened. All of the matching bolts must be installed in the same direction(for example: all bolt heads on one side and all nuts on the other side). I just fixed this problem on my car this weekend. I had a viration in the drivetrain and I found a loose bolt, probably because of previous wheelhop and racing. I tightened the bolt and problem solved. The springs will NEVER cause a vibration unless you drop the car 4 inches and slowly damage the axles, then it might lead to a viration. Have those bolts checked


Hope this helps, jrrod

To speculate, I agree with you. My gut level is the picture he is showing of the subframe may be normal. All the pictures I have of these bushings are ones in the air and there is no gap. But there again, you have 200-300 lbs of downward force. I have not paid attention to them when they are on the ground. I will however.

But can movement of these important bushings be controlled? Yes, and in the case of the poster, shoule be easily controll by using a Pedders EP1200 insert, due to the hp he is running. But of coarse, everything MUST be checked to make sure the bolts are all tight. This is really critical. But again, unless the bolts are loose, I do not think they are the issue here.

mike
dms

[Ltdodge]

car is at another dealership, lets see if they can find the issue, so far i have had no such luck with 3 locations. so far they were busy and the service adviser told me that the tech drove it and notices the vibrations and they will be looking at it closely tomorrow. I also have the car in for an oil leak I found at the dyno shop.....

man this car is cursed , I dont mind paying for repairs but i don't want to pay for other items just to try to find the root of the problem. i wish I had a shop with knowledge of the 2010 camaro near the area. i will keep you posted on the results.