Rear wheel lock up.

[Turtle]

My bro was driving the 240sx and it had loose lug nuts, I went to change the wheel and, when I tightend them down, the wheel locked up. I'm thinking it could of been because of the loose lug nuts? I took the wheel off and the rotor spun easily, but with the wheel tightend it gets stuck. I've had these wheels since I bought the car so it can't be wrong fitment. Any suggestions on what it could possibly be? :-/

[murda-c]

you probably warped your rotors. badly.

[Turtle]

Could it be that my brakes are gone? The pad is grinding the metal, I was taking my car to the front to change brakes and, my wheel had a flat and I changed it when I tightend the lug nuts the wheels locked up. Could it be that the tightening of the wheel caused the rotor to scrape on the caliper cause it to lock? Just a thought.

[SiI40sx]

A very common problem with 240s is the rear capliers seizing up. But what Im confused about is you say that your rotor spins freely? When do the wheels lock up?

[racepar1]

Since the rear wheel was loose the caliper piston most likely had to extend further to contact the rotor. On the 240's the rear caliper pistons don't press back in you have to turn them with a tool. So what is most likely happening is that the piston is over extended and since it won't press back in it is locking up the wheel. You have to take the caliper off and get the tool to screw it back in a bit and you should be fine.

[Turtle]

But, the wheel only locks up when the lug nuts are tightend... Could it be tightening the wheel the rotor will scrape the caliper causing it to get stuck while its tighend?

[racepar1]

That's because without the lugs tight the rotor is not pressed all the way up against the hub.

[Turtle]

Ok, let me see if I get this right.

Yesterday I parked my car at the back yard and got a flat.
My bro changed the tire and left the lug nuts loose and drove it around like that.
He gets home I have another tire to put on and I put it on.
When I'm putting the tire on I notice I have no brakes left at all, the bare pad is scrapping the rotor.
I put the wheel on tighten the lug nuts and drop the car.
I try moving it to the front yard to change the brakes and the car doesn't move.
I notice the car is throwing up dirt open my door and the wheel is locked up.
I jack the car up try turning the wheel with my hands and no budge.
I loosen the lug nuts to take the wheel off and the wheel spins easily.

I hope that sort of clears things up cause I sort of don't understand what you mean.

EDIT: Could it be that the tightening of the lug nuts cause the rotor to scrape on the caliper because no pad is left?

[GSXRJJordan]

Since the rear wheel was loose the caliper piston most likely had to extend further to contact the rotor. On the 240's the rear caliper pistons don't press back in you have to turn them with a tool. So what is most likely happening is that the piston is over extended and since it won't press back in it is locking up the wheel. You have to take the caliper off and get the tool to screw it back in a bit and you should be fine.

Quoted because this is most likely the answer. Screw the pistons back out and then put the wheel on.

Either that or your wheels are actually hung up on the caliper - but you said they used to be fine, so ^^^^ do that.

[Turtle]

One more question this time its my bros 240sx. I keep thinking its the booster thats wrong. My bro and I went to El Mirage and on our way back home his brake booster line broke in 3 places. In order to get back home he taped it back up (I know ghetto.) Well he drove it like that for a while. When he was coming back from work his car began to slow down. The brake lights were on and the pedal was stiff as hell. Even when the car was off the brake lights were on. You can drive for like 5 minutes but then the rotors glow red hot. Not warped and the brakes seize. =/ Suggestions on what could be wrong?

[Turtle]

Oh, uhmm z32 brakes slotted rotors, performance pads and SS brake lines.

[Turtle]

Anybody think that it can also be the brake booster? Help please.

[Turtle]

Hey, I changed the brakes today and noticed rotor had no more than 1/8'' to go so it can reach the other side, well anyways, I changed my brakes and now my hand brake doesn't work. I used to step on the pedal about half way to feel any braking so when I changed the brakes I went out of a test drive and, stomped on the pedal like I used to and almost flew out the window! So now the car brakes like a champ but my emergency brake doesn't work when I yank it. I spun the piston in so I could put the brakes and it was a bit loose when I bolted it all down. Could it be that? My dad said that it will go out again and begin to brake but, I was driving for like 10 minutes yanking the e-brake and no dice... Help. =]

[Turtle]

Oh, I changed the rotors also to drilled and slotted ones. =\

EDIT: Also, my pedal is basically dead on cold starts when the car warms up the pedal slowly reincarnates itself...:tweak:

[GSXRJJordan]

^^^ dead pedal sounds like vacuum issues, or bad brake booster.

[racepar1]

On the question about the booster you are right. The booster is most likely the problem, not the wrong booster necessarily but a bad booster. I have seen this problem before on a toyota truck and it was a bad booster. As far as the e-brake question it is most likely mis-adjusted. There are two adjustments, one at the calipers and one at the handle. The wheel coming loose could have screwed something up so inspect the cables and adjustment very closely.