I have a 2000 civic SI boosted and under accelartaion ( mostly between 60 - 80 ) the car shakes real bad, drives straight, just shakes bad. It put down 282 WHP and 198 LB TQ on a mustang dyno. My question is should I get OEM axles or aftermarket? am I making to much for OEM axles to handle? and should I replace the wheel bearing hub assembly while im doin the axles?

 

Are you sure its axles?
There are people runing much higher hp than you.

 

Yes I realize the HP thing, im not entirly sure its the axles, maybe wheel bearings was my next guess... Ive had the tires rotated and balanced twice already. Just eliminating the easiest things first. As of last week every now and then when the clutch engages and i start to move forward I get a clunking noise... Possibly the back motor mount?

 

My friends old car would vibrate a lot, after switching the all the motor mounts (inovative), it stoped a lot of it.

Have you checked to see if the bearngs are bad? Or maybe on their way?

You heading the right direction checking easy things first.

 

Motor mounts is my next option. I have energy suspension inserts on all them, just not the rear one ( I know its the most important, just ran outta time ) but I have the insert for the rear mount in my garage, I just work 12 hour shifts so time is an issue. Prolly just have a shop do it

 

Damn, I feel your pain, kind of. Lol

Useing the inserts you should expect some sort of vibrations.

 

Don't just throw parts at it man. Diagnose and then buy parts. I had a vibration problem...it was a bent hub.

 

OEM B series axles will support either 600 or 800WHP, I cant remember which. Its all about driving skill. Anyways try checking simple things. It could be a tie rod, maybe even a wheel off balance. Theres a lot of things that can make a car shake. Lift the front of the car up. Grab the tire at 12 and 6 then try to puh and pull. If it moves you need a wheel bearing. Grab it at 3 and 9 and push and pull. If it moves you need a tie rod. If its neither the 1st thing I would check is the wheel balance.

 

I also recommend that you attempt to find out what isn't right before replacing parts, but one of the telltale signs of a bad inner CV joint is vibration during acceleration.

I have replaced an axle with one from an auto parts store, that didn't have the rubber balancer/damper the factory one did, and I believe the replacement axle may have introduced slightly more vibration during acceleration. Maybe one of these days I'll see if I can have it replaced under the lifetime warranty.

 

Wheels have been balanced twice. the balancing took away the pull but not the shaking. Ill check the tie rods and wheel bearings though.

 

axles.
what kind do you have right now?
i swapped out my oem ones for aftermarket because of a ripped boot only to be surprised by a second and third gear vibration under load

 

Just OEM ones... so it turns out I have a torn axle boot, didnt get all the way under. im pretty sure its the axles at this point though. Would explain the clunking noise when I roll from a dead stop in reverse and going forward

 

As said above, vibration under acceleration is a tell-tale sign of bad inner CV joints. Get under the car and grab the axle shaft in one hand and the inner joint cup in the other, and rotate them against each other to check for free play. There should be absolutely zero play between the shaft and the inner joint. Even the slightest bit can cause vibration during acceleration.

Remanufactured axles are really a hit or miss. I went through 3 sets in 2004 that all had bad inner joints straight out of the box. On the 4th set (same brand) I finally got some decent ones and had no problems at all for 3-4 years. I'm not totally sure but I think I'm still on the same left axle that I got back in 2004. The right one has been replaced once in 2008 I think.

From now on I will only get brand new axles, just not OEM Honda ones. I recently put brand new GSK axles on our 96 Corolla and have had zero problems from those. That car also vibrated under load at highways speeds, and the new axles cured it right up.

As for the amount of power you're making, new OEM replacement axles will probably work just fine, but don't hold me to that. Many people here on H-T swear by Raxles CV axles, even if they're not making big power over stock, but those get pretty expensive compared to even new OEM replacements such as GSK brand.

 

Thanks for all the input. Im gonna fill in my rear motor mount and change axles!