It Broke

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Driving my 1999 cobra and I developed a major driveline vibration starting around 60mph. Just last week I was cruising Highway speeds comfortably with no shakes.

The shake starts at 60 mph. It feels like driveline. Had it on a lift today at a shop and ran it till 60mph. Shook on this lift. The mechanic thought the driveshaft had somethiing loose inside it. Since the shake devolped I have had the ujoints changed and the driveshaft balanced by a reputable driveshaft shop. The DS shop happened to be in the same area as the shop i stopped at, and a guy from the DS shop inspected the DS saying that the noise was coming from Tranny on the hoist while running the car to 60 again.

*** the shake occurred after I replaced the u joints

The DS slipped right out, and slipped right back in during install. Nothing seemed abnormal.

Took it to another shop had it on the lift. The shop didnt spot much play in my yoke going to the tranny. What the guy did say was that my rear IRS cv axles have too much play. Causing vibration, working its way up to the DS up to the tranny.

I am at a loss for words. Need some knowledgeable input.

 

[Martel]

Check cv shaft retaining nuts 240-250 ft. lbs torque
check cv shaft bearings
check cv shaft joints
check tire balance
check tires

I think those are good staring points.

 

[boostedvert]

somewhere in that post may lie my answer

 

[Black*Death]

As mentioned....i am guessing half shaft retaining nut(s). good easy place to start with....250 ft. lbs is a decent amount of torque with a torque wrench...

 

[boostedvert]

With the axle nuts tights he problem persists. This problem came up after I pulled the driveshaft for new u joints and had it balanced. Prior to removing the shaft the car was driving smooth at highway speeds. I suspect driveshaft because the problem wasn't there before removing it. Haven't driven the car hard since the drivehaft went back in. Also for all us 99 guys, advance auto has our half shafts for 60 dollars!!!!! New.

 

[OldSVTGuy]

Try clocking the driveshaft at different positions. This has helped some. Good luck....

Whenever I remove my DS, I mark it so that it goes back in exactly the same way it came out.