Noise at 70mph?

[joeseth]

Since I put steelies on the back I've had a really bad droning/vibrating at 70mph. I gets so loud I avoid 70 alot. I gets better above 70. Tried putting some old alloys on the back and it did make it alot better. But when I swapped the steels round with other steels it still made the noise? Could they just be badly balanced or really noisy tread (i've never used the steels before)? Or could a rear wheel bearing be on the way out (has been making a slight noise since I bought the car) and the steels excentuate it?

Any opinions would be appreciated. Thanks, Joe.

[Morat]

Wheel balance, especially at 70. That seems to be the speed for unbalanced rears to get noisy.
But check your wheel nuts first!

[Funnybear]

Could be the rear diff as well. Had mine sorted recently and made a hell of a difference.

[TPS]

But check your wheel nuts first!

+1 , thats happened to me before!

[joeseth]

Got wheels balanced but hasn't made a difference. There's to much vibration for it to just be road noise from the tyres. Could be the diff I suppose? How do you check if wheel bearing has gone? I'll prob take to a garage if its wheel bearing because cant be bothered with trying to press them in/out myself.

[Funnybear]

I had my diff sorted when I had the rear bushings done recently and it made one hell of a difference. I'm fairly sure he just stuck more oil in it, but by god, it was a different car that I got back.

[Captain_Birdseye]

I had my diff sorted when I had the rear bushings done recently and it made one hell of a difference. I'm fairly sure he just stuck more oil in it, but by god, it was a different car that I got back.

Faster?

[joeseth]

Im guessing the filler cap is on the top and you have to take the diff out to refill? Mines just an open diff if that makes a difference.

[Brianmoooore]

Im guessing the filler cap is on the top and you have to take the diff out to refill? Mines just an open diff if that makes a difference.

Filler plug is half way up the back, and easily accessible. Buy your oil in the type of squeezy bottle that has a 5" plastic tube attached to it.
Push the pipe through the filler, and squeeze until oil starts coming back out.

[joeseth]

So I don't need to drain he old oil just fill it right up (well to the level of filler cap)? Cheers Brian, very helpful!

[Funnybear]

I had my diff sorted when I had the rear bushings done recently and it made one hell of a difference. I'm fairly sure he just stuck more oil in it, but by god, it was a different car that I got back.

Faster?

I do believe it was. But I think thats more to do with that my right foot is slightly more trusting of the back end now.

[thecode]

Easy fix do 69 MPH

[steve_k]

So I don't need to drain he old oil just fill it right up (well to the level of filler cap)? Cheers Brian, very helpful!

drain the old oil first, then refill with new oil, no point mixing new clean oil with old sludge,