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Subframe lock bolts install = fail

Posted: Sun Mar 09, 2008 9:52 am
by jamal
Well, today I gave the Whiteline rear subframe lock bolts another try.

This invention helped a lot:

Image

I used it to clean out the dirty and rusty threaded holes in the chassis, and it worked great. I got the passenger side to start threading, and after a bit more work the other side seemed to be going in.

I gradually tightened things down, but the subframe seemed a bit mis-aligned so I backed all the bolts out and wiggled things around and then started tightening things.

Then I did something really retarded.

I was getting impatient and grabbed the impact gun. Neither bolt went far so I backed them out.

Image

And that's the end of that.

I think I'll try the perrin or sti or group N subframe bushings next.

Posted: Sun Mar 09, 2008 10:05 am
by Arctic Assassian
lol. I did that with a wheel stud on an 05 outback. I did not make time on that tire changeover.

Posted: Sun Mar 09, 2008 3:33 pm
by Legacy777
You did loosen up the four main bolts holding the subframe in place, didn't you?

Posted: Sun Mar 09, 2008 4:44 pm
by evolutionmovement
That sucks! At least you learned the hard lesson about impact guns. Probably about the same way most of us have.

Posted: Sun Mar 09, 2008 7:54 pm
by ericem
What that they have alot of powa??

Well that sucks.

Posted: Sun Mar 09, 2008 8:33 pm
by evolutionmovement
Yes. A lack of patience in getting bolts properly threaded into clean holes first strips them quick and hard. I've done it a couple times myself and I'm usually pretty careful. Sometimes it's just the threads have shit in them that causes it as well. It was smart to clean the holes out first regardless of the outcome.

Posted: Mon Mar 10, 2008 12:12 am
by jamal
It was a really weak electric gun. I didn't cross-thread it either. It just stuck on the subframe and stripped the threads.

And yes everything was very loose and well-lubricated.

Posted: Mon Mar 10, 2008 2:24 am
by evolutionmovement
Oh, I see, the subframe caused the misalignment of the bolt in the hole. That sucks.

Posted: Mon Mar 10, 2008 3:36 am
by IronMonkeyL255
:lol:

We snapped one of those buggers in my uncle's RS trying to put it in.

I have a set awaiting install in my SS, and I'm not looking forward to it.

Posted: Mon Mar 10, 2008 2:38 pm
by Brat4by4
Sounds like you need to run a tap through those threads. You can make one yourself, just cut a couple of reliefs down the threads of another bolt with the same pitch.

Posted: Mon Mar 10, 2008 4:23 pm
by Arctic Assassian
it's not the threads, its the fact that the geometry of the hole changes as you try to put it in. If the car is on a lift and you have three people, its easy as pie. But life is not so kind sometimes.

Posted: Mon Mar 10, 2008 4:54 pm
by n2x4
I did the same thing when I was swapping my tranny. Used the impact gun on the tranny crossmember bolts. The next bolt I used after I got the threads cleaned broke off so I had to cut off the head, weld it in place, and add a nut on the other end. We learn the hard way I guess.

Posted: Mon Mar 10, 2008 6:18 pm
by Legacy777
I make it a point not to install bolts with impact guns......only use them for disassembly.

I'll use impact guns to take up the slack if I have a long bolt, but like I said, once that's done, I switch over the hand tools.

Posted: Wed Mar 12, 2008 11:20 pm
by farfrumwork
I guess I was lucky, as I installed my lock bolts in my old carport in 15min with no hassles.

I didn't chase the threads or lube anything.
It was so painless, I really can't even remember doing it :wink:

sorry about your issues though. Get another set - maybe find some used. They tighten up the rear nicely!

Posted: Thu Mar 13, 2008 3:01 am
by jamal
yeah I think the threads might still be okay. I'll just find someone who had a similar problem, buy their good bolt, and try it again I guess.

Posted: Thu Mar 13, 2008 3:47 am
by livestrong14
Hey Jamal, will the PERRIN subframe bushing kit fit our cars?

Posted: Thu Mar 13, 2008 4:26 am
by jamal
The lock bolt things will but I don't think the diff bushings do. So it's cheaper to just get the whiteline bolts.

I originally thought they were urethane subframe bushings but they are actually for the diff.

You can get group N subframe to chassis bushings but they're $15 each so it's generally cheaper and easier to get the lock bolts. Assuming you can get them to go in.

Posted: Thu Mar 13, 2008 4:43 am
by Adam West
Jamal, what's the Whiteline part number on those, I need to order some...

Posted: Thu Mar 13, 2008 5:31 am
by ericem
Pardon my lack of reading but um, whats the point of the locking bolts anyway??

Posted: Thu Mar 13, 2008 5:35 am
by jamal
The rear subframe is connected to the chassis with rubber bushings. The bolts lock it into place to keep things from shifting around under cornering load.

I guess I could make replacement bushings out of delrin...

Posted: Thu Mar 13, 2008 3:52 pm
by n2x4
jamal wrote: I guess I could make replacement bushings out of delrin...
I'd buy some.

Posted: Thu Mar 13, 2008 10:17 pm
by jamal
Adam West wrote:Jamal, what's the Whiteline part number on those, I need to order some...
Do I look like a whiteline catalog?

Oh wait, maybe I do.

KCA750 off the top of my head.

Edit: KSB750.

so close.

Posted: Thu Mar 13, 2008 10:22 pm
by Adam West
I thought you were "Joe Whiteline" <grin>

Thanks. I thought it was that one but some sites say they are for some version of WRX's only - I knew that was wrong...

Posted: Fri Mar 14, 2008 6:16 am
by Adam West
Here's another set to consider...Might be a bit more forgiving design?

http://www.groupa.ca/PR_lockingbolts.html

Re: Subframe lock bolts install = DIY WIN (no fail)

Posted: Fri Nov 18, 2011 8:09 pm
by dkopp
hey kiddies,

i followed this DIY mod last night and had ZERO problems. bolts were just under $16 at Lowes. the thrust flange bearings were reasonably priced at Lowes, but the carriage bolts were about 4x the price compared to McMasters or Boltdepot, but you have to factor in shipping and time. certainly less than you'll pay ordering from from one of the manufacturers.

couple clarifications:

grade 8.8 is the strongest designation i found online for a bolt with a 1.25 fine thread pitch. someone please correct me if they find grade 10.9 in fine thread metric in an M12 bolt of any kind (carriage or hex).

you must, MUST, M U S T, chase the threads before installing, and chase them twice. blow them out in between and spray it down heavily with penetrating liquid or cutting oil propellent. even after chasing threads, it was still very slow in torquing it down. take your time and do it properly. a quick inspection in the pilot hole should show you that the years of use have mostly obliterated the threads. you really are re-cutting them.

my subframe was aligned and i didn't need to loosen anything. just jacked the rear for jack stands and crawled under last night with an LED flashlight. it was probably in the 30's.

result: rear hooks up solidly. a very good $16 mod.

DIY link: NASIOC

http://forums.nasioc.com/forums/showthr ... ?t=2183600

Install instructions: NASIOC

http://forums.nasioc.com/forums/showthr ... ?t=1752267

be careful out there, and as always, i assume or accept no responsibility or liability for your actions in modifying your car. please know what you are doing or ask questions. be safe!