Cross Threaded a Seat Bolt.

Installing seat lifters. Caught it just a little too late.

Now the nut is putzed. Anybody replace these? How?

The only option I can think of is to drillout the threads of the body nut and use a lock nut with a longer bolt.

 

Tap

 

I second the tap, if you know the correct pitch, you can fix the threads.

 

I think it's a 10mm fine

 

Turn it more. Free loctite

 

Do the bolt holes to through the floor boards, like can you see the nut from under the vehicle? If so run either the bolt or correct tap up threw the nut using the good threads at the bottom to safely start.

 

Use a thread chaser. A tap is for cutting threads. A chaser is for restoring them.

 

From looking at the nut from underneath there is some form of a plug. Not sure it can be removed or how. I think it would interfere with a thread chaser.

 

If it won’t interfere with a tap, it won’t interfere with a chaser.

 

I’ve never had much luck with thread chasers. Except if the threads are still very good and only dirty. Since the hole is damaged by cross threading, the threads are damaged but not a lost cause. You could somewhat repair the hole with a tap. Since there’s a plug at the bottom, the metal shavings are going to stay in the hole instead of falling out the bottom. You’ll have to be very patient. Turn the tap, blow out the metal shavings, repeat. Tapex does wonders. You could do it with a starter tap, then a bottom tap. Then look closely at the threads. If it’s too far gone, trying to tighten a bolt in it will just rip out the remaining threads. If you’re lucky a bolt will tighten. If not a helicoil thread repair insert is next. If you’ve never done it, get help. Or tap it out to the next larger bolt that’ll fit the seat. I’d stay with fine thread type.

Use good quality bolts. Seat bolts feel heavy because they’re dense and strong. In the event of an accident, you don’t want to go flying into the windshield because the cheap bolts you got broke.

 

I’d try a plug tap if it isn’t a through hole.

 

Clean up the threads with a tap or a chase. If they are seriously putzed, put a heli-coil in. Remember to use some cutting fluid with the tap.
As a side note, be sure you are using at least a 10.9 bolt and preferably a 12.9. I have seen 8.8 or lower class bolts used on jackers which is a terrible idea for a safety system. I know lots of people like the jackers, but using a spacer in a single shear mount isn’t a great idea for maintaining rigidity.

 

Cross threading is as good as locktite one time. Just leave it?

 

Not the only option, but, the fastest, easiest and cheapest (if you don't already have taps and dies). it will work as well as a thread restoration, and know one will no except you.

 

It's my daily driver and I didn't feel it was a good idea to drive around with 3 bolts so I put the original bolt back in. After several tries I couldn't get the original threads to catch and ended up torquing it in anyway.

Hopefully somebody who has replaced the seat nut will see this and pipe up.

Thanks for the replies.

 

I'm pretty sure it's tack welded to the bottom of the cab. Grind it off and weld on a new nut, problem solved.

 

OMG. I have no words.

 

Neither do I ....... not understate the obvious, as I'm sure you are aware; your inboard seat belt (the buckle) anchors on the seat frame making the seat attaching bolts an integral part of the seat belt system. What you have a seat bolt that likely has no more holding power than if you had driven it back into the hole with hammer.

 

Is it a rear of the seat bolt that goes through to the bottom of the body? If so, longer bolt and extra nut n call it good.

 

Give it a couple of ugga duggas. Cross threading is free loctite.