HELP i think i cross threaded subframe mounts

[JS3690]

I literally just had this happen to me, except it was the front passenger rear subframe bolt I stripped. a real pain in the ass. at least half the threads are gone. gonna try and retap and if not helicoil this thing.

[Dembo]

Also wish I'd read this first. Right hand side wasn't a problem, left hand side now buggered. I don't know how much damage I've done trying to get it in.

[Shady195]

I've also done this doing my subframe bushing inserts. Unfortunately me being me, I got about 3/4 of the way in before it started to happen. I fucked with it for a good 2 hours before I just sent those bolts home with an impact. I actually took them back out too. The threads on the bolts deff got cut a little different but it did not strip them, it did not appear to actually strip the hole in the frame rail either. Looks like subaru was smart, bolt is softer.

I ordered new bolts anyways, as long as I don't have any issues Im going to leave it as is. However if I own this car and doing anything 20 years down the road im probably going to remember this day and hate myself.

[Tor]

I have those bushing inserts lying around too. It the benefit worth the risk?

Also, a similar thing happened to me with the front subframe bolts, when I was installing a new swaybar. One of the bolts got stuck about 3/4 in. Backed it out and the very upper part of the thread had some damage. I am guessing some debris may have been present in the thread.

Hence, one piece of advice that might work here too: CLEAN the threads THOROUGHLY with compressed air before installing the bolts.

Bolt went in afterwards, but with significantly more force required than the others.

[zc06_kisstherain]

Originally Posted by autoCAR

he is a friend of the family, and he saw I was genuinely upset about the whole thing, so he didn't charge me. I tried leaving him 100 bucks but he didn't take it

i will PM you when i have problem so i can take you there with me..lol
glad that you got it fixed.

I dont see myself working on bushing though..way too much work and hassle unless i have no life but working on car.

[Shady195]

Originally Posted by Tor

I have those bushing inserts lying around too. It the benefit worth the risk?

Also, a similar thing happened to me with the front subframe bolts, when I was installing a new swaybar. One of the bolts got stuck about 3/4 in. Backed it out and the very upper part of the thread had some damage. I am guessing some debris may have been present in the thread.

Hence, one piece of advice that might work here too: CLEAN the threads THOROUGHLY with compressed air before installing the bolts.

Bolt went in afterwards, but with significantly more force required than the others.

After a few days, I can say I personally think so. I do have some increased NVH, however I did the differential outrigger set and have heard that this is the major cause of NVH increase with the subframe bushings.

Gear changes under heavy acceleration feel much better, rev matches feel smoother, the ass feels a lot more stable when hitting bumps when loaded up in a turn.

[Tor]

Thanks @Shady195

In preparation for the install I'll order new bolts. From my experience with the front, I am guessing a likely cause of the problem are rusted bolts. Some rust debris getting caught in the thread and causing damage?

Should I go ahead and directly get an M14x1.5 tap too and run the tap through before reinstalling the bolts? Or is that overkill?

..and if you recommend getting one: What is the minimum length it needs to be to get access without having to take the subframe out completely? Would 7 cm length be enough? Like e.g. [ame="http://www.amazon.de/PROFI-Gewindebohrer-Satz-HSSG-teilig/dp/B002OEPBYK/ref=cm_cr_arp_d_product_top?ie=UTF8"]this one[/ame].

[FrostedFlakes]

This nearly happened to me two years ago. I had to jack up the front of the subframe a little to get things back aligned. If something does not feel right do not force it.

Bushings need to be cleaned and touched up with grease every few years or when they start to squeek. If you had a hard time installing I suggest getting a shop to help in the future when you need to check it again.

Those bolts also needs to be inspected. They are prone to corrosion and oxidation due to exposure to moisture in that area for some reason. I had to use a scotch pad and clean the bolts lightly before overkilling it with antiseize to prevent future rust.

[Limey]

Adding myself to the list of those who had to have both rear threads re-tapped after mucking up the install. If you're doing this in the Bay Area, go to Pit Row on Lafayette in Santa Clara. The folks that run the place are great. Dennis had a 14x1.5 tap shipped in quickly and got me back on the road today. It's still at the shop if anyone else needs to use it during their visit. It helps to have two people with one to align the subframe while the other wrenches. I found it hard to align the frame even when supported with stands.


Sent from my iPad using Tapatalk

[Tor]

Installed mine today and made a video.

If anyone needs help installing these, I started a DYI here:
http://www.ft86club.com/forums/showthread.php?p=2865605

[wheelhaus]

I managed To crossthread my left rear subframe bolt sometime last year. F'd it really good. Tried chasing the threads with a tap, no good, all the remaining threads sheared as soon as I got a little torque on the bolt. Had to order a Timesert thread repair kit and it went as smooth as butter. Total cost was like $150-160. I can post the part numbers if anyone is interested.

[Shady195]

Originally Posted by wheelhaus

I managed To crossthread my left rear subframe bolt sometime last year. F'd it really good. Tried chasing the threads with a tap, no good, all the remaining threads sheared as soon as I got a little torque on the bolt. Had to order a Timesert thread repair kit and it went as smooth as butter. Total cost was like $150-160. I can post the part numbers if anyone is interested.

Deff

I'm sure I'm going to need to do it at sompoint. There will be a time where I want to completely change those bushings out and I sent that 1 fucker home hard. I'll probably snap it and have to drill and tap it.

[wheelhaus]

Here's the TIME-Sert info page. http://www.time-sert.com/metric-kits/

I ordered my Time-sert kit and parts from Belmetric. Here is everything 14x1.5.
https://www.belmetric.com/m14x15-c-217_218_242/

1x TS1415 - thread insert kit
1x TS14158 - M14X1.5X24.5 insert (deeper than what comes with the kit)
1x TS34155 - M14X1.5 Tap Guide (not required, but good peace of mind)
also...
1x TAPWRENCH74 (This is not a time-sert part, this is just a ratcheting T-handle tap wrench from Belmetric. It required modification to fit the taps that came with the Time-sert kit, the wrench's wedges needed to be filed open by a mm or two. Bit of a headache, and ultimately it worked, but the TAPWRENCH34 may work better as it's designed to fit taps larger than 1/2".

Please note, using this threading kit, you will need to lower the subframe away from the chassis to make room for a drill and tapping tools. I made a wood support tray, using standard 2x6 and some 1/2" plywood/OSB. It supported the subframe with a single jack and was manageable by simply removing the lower shock bolts and brake line/ABS line clips; drive shaft remains connected. If this makes you nervous, you should disconnect everything.

This tray balanced and supported the entire subframe by supporting the weight from slightly forward of the diff's jack point. In the pics you can see the jack tray and subframe lowered from the chassis. You can adjust the position of the jack until you can feel the weight is stable and supported evenly front to rear. PLEASE BE EXTREMELY CAREFUL if you leave lines connected or you may be replacing ABS wires and brake lines if you're clumsy and knock the subframe off the jack. You can move it around a few inches, but the ideas is that you only need enough room to get a drill inline with the chassis.

Tray info:
33.5" wide
5" wide risers on each end
plywood feet 5x11" and reach forward

I can provide a complete walkthrough if necessary... but the Time-sert instructions are pretty clear. only difficulty is getting access.

[Bodalenko]

I put the rear sudframes Whiteline in on Saturday and realised it was an install that was out of my league when I had trouble getting the rear bolts lined up. Took it to a place i get my alignments done thinking that a proper suspension place would have no issues. What does the young guy working on my car do? Despite me warning him about making sure the bolts were lined up exactly, after undoing the rear bolts he ignores what I told hm, and the pictures from this forum showing how to do it, and cross threads the right hand front bolt when it was about 3/4 home. Finished up using a thread file and saved the bolt thread so it ended up ok. I didn't have the opportunity to test what difference the sub frame and diff supports, I had both done at the same time, have actually improved if anything but to those considering the upgrade, this is NOT anywhere near as easy as one would think. To look at the instructions it looks as simple as unbolt, lower, install bushing supports, insert bolt and torque. As soon as you loosen and the remove the bolts the subframe will move, even if it's just a mm, and that mm movement will be the difference between success and heart break. In other locations you can get away with a cross thread. On the subframe a serious cross threading means the car basically can't be moved, even with 3 good bolts. You have been warned!! Anyone trying this now has as many experiences, facts, and info as physically possible. Key is to take your time, do not force the bolts, have the car high enough to actually see the holes, and do not think because the bolts screw in an inch they won't still cross thread. And don't use power tools under any circumstances!!! Oh and buy a rubber mallet cause chances are you'll need it