So, I replaced my rear subframe recently and whilst there changed the engine bushes and put on some hardrace rear control arms. I know the tracking needs doing, but when I went for a test drive to make sure all was well the back end was pulling severely to the right under any braking.
Is this likely to be the tracking? I'm currently putting on new wishbones so can get the tracking done yet.
under braking sounds like a brake problem to me.... Checked the hoses are okay? Stuck/sticky calliper? Greasy disc?
It could be the suspension - but until you get it checked, best to start with the brakes.
Have you go an IR temp sensor? You could use that to measure the heat in the brakes after an enthusiastic (as you dare) session and that'll tell you if anything isn't in balance... a good idea that I've come across is to wind the calipers all the way out without the discs in and put red grease around the piston. Do that a couple of times and then try the braking?
Quote from: M.J.S on January 2, 2019, 15:36
under braking sounds like a brake problem to me.... Checked the hoses are okay? Stuck/sticky calliper? Greasy disc?
I hope not, it's only since I've replaced the subframe/arms. I put new discs and pads all around about 6 months ago.
It's a very odd sensation. As if the back end is trying to overtake me
Quote from: dan944 on January 2, 2019, 15:39
It's a very odd sensation. As if the back end is trying to overtake me
I think I've had that - it's butt clenchingly scary.. All you can do is check the torque values on your suspension until you get it aligned and recheck the action of the caliper piston.
Quote from: jvanzyl on January 2, 2019, 15:39
It could be the suspension - but until you get it checked, best to start with the brakes.
Have you go an IR temp sensor? You could use that to measure the heat in the brakes after an enthusiastic (as you dare) session and that'll tell you if anything isn't in balance... a good idea that I've come across is to wind the calipers all the way out without the discs in and put red grease around the piston. Do that a couple of times and then try the braking?
Tbh I wouldn't go more than 20mph as it's that bad. I don't want to be winding back callipers [emoji1751][emoji3603] lol. Well I'm off the road for a while now anyway I guess. So will see what's going on.
Is it worth checking things like tyre pressure and making sure you've got them on the correct side of the car if they have an inside/outside marked as well?
Quote from: M.J.S on January 2, 2019, 15:50
Is it worth checking things like tyre pressure and making sure you've got them on the correct side of the car if they have an inside/outside marked as well?
When I'm talking about the back end pulling to one side it's quite literally moving the whole car very dramatically.
The first time it happened I pulled over and triple checked everything as I honestly though the subframe had come off.
I'm hoping it's tracking but unsure as it's pretty catastrophic. I'll definitely need to give the brakes a good check over though.
Wow, that does not sound like any fun whatsoever.
Good luck in finding what is it.
It sounds as though something is effing loose!
Tracking would have to be utterly miles out to cause that.
Go over every bolt at the rear and torque to specs. Then (as you say) check all the brakes with the car off the ground.You can check front and then rear, if you don't have enough jack-stands.
Once you start really looking it should be bloody obvious.
Edit: In fact, get a pry-bar on the job and check every joint and bush.
iirc as my memory is quite bad, someone else had a problem like this after a rear member change and it was a loose nut, they torqued it up but it still wasn't tight enough. I'd suggest putting a torpedo level on the wheels just as quick reference, to see if they're massively out.
Thanks guys.
I'll give it another once over and check all nuts and bolts tomorrow.
The arms are completely new to my car so could be miles out of tracking. I can't drive it until I sort the wishbone so I shall keep this updated.
Quote from: wotugonado on January 2, 2019, 17:41
iirc as my memory is quite bad, someone else had a problem like this after a rear member change and it was a loose nut, they torqued it up but it still wasn't tight enough. I'd suggest putting a torpedo level on the wheels just as quick reference, to see if they're massively out.
Your memory is good.
https://www.mr2roc.org/forum/index.php?topic=62761.0
Thank you very much.
I'll torque the hell out of these on Friday and hopefully be ok again.
JB
Beat me to it.
Dan. Maybe try contacting tos. Compare notes.
I'm going with. It was ok before the parts swap so likely to be related.
Always require a geo after a sub frame. Bringing diff arms into the equation as well.
But might as well start with torque settings.
Least you can rule that out.
Quote from: Ardent on January 2, 2019, 18:48
JB
Beat me to it.
Dan. Maybe try contacting tos. Compare notes.
I'm going with. It was ok before the parts swap so likely to be related.
Always require a geo after a sub frame. Bringing diff arms into the equation as well.
But might as well start with torque settings.
Least you can rule that out.
That's my principle as well. I knew it would drive awful but the way it felt I wanted to make sure it was more than tracking. I'd have hated to waste the money.
I had the same. Tight bolt wasn't tight enough on one of the suspension arms after I did subframe.
For suspension.. Get the torque values and get it set right.
TOS and I both had this when we changed the sub frame. Both were cured be retightening all the bolts especially the suspension arms.
Just waiting for my blowtorch to turn up before I get dirty :) sounds like a fairly quick fix which is good :)