Trying to source replacement T55 seat bolt for 07

[ThermionicEmissions]

Hi all,
So last weekend I discovered the floorpan of my 07 supercab is rotting out due to moisture trapped in the insulation under the vinyl flooring. In my efforts to remove the seats and flooring, I stripped one of the 4 T55 bolts which mount the front of the seats to the floor. Took it to my local shop who ended up having to drill it out and put in a heli-coil. Anyhow, I am now short a T55 bolt, but cannot seem to find these anywhere. Anybody have any ideas?
Anyone have spares from a parts truck they'd want to sell?

The floor is another matter completely. No sign of a leak that caused the moisture, and we've had a few good downpours the last few days. I suspect the previous owner hosed off the vinyl floor regularly.
I've been watching a lot of welding videos lately...

 

[eddieq]

Salvage yard? Otherwise, take one of the others to the hardware store and find a bolt of the same diameter and thread and use that. Doesn't have to have a Torx 55 head. Could be a hex bolt.

 

[Grumpaw]

Torx bolts are metric thread.
A T-55 torx equates to a 12 x 1.25 thread. You can replace the torx with a regular metric 12 x 1.25 hex head bolt of the appropriate length.
But, reading your post you state a helicoil was inserted. You need to know what size/thread the helicoil is. Very possible the shop didn't use a metric 12 x 1.25 helicoil as it's a size not readily used.
Possible they used an SAE helicoil. You need to find out.

 

[Curious Hound]

Torx bolts are metric thread.
A T-55 torx equates to a 12 x 1.25 thread. You can replace the torx with a regular metric 12 x 1.25 hex head bolt of the appropriate length.

Try to get grade 8.8 or 12.9 bolts. That is a strength grade similar to SAE grade 5 or 8 or whatever.

 

[Grumpaw]

If you have trouble finding the right size, there is an alternative.
I believe the nuts are just spot welded to the floor, and the bolt hole goes thru the floor pan. Just get the largest grade 5 bolt that will fit thru the inserted helicoil, with an xtra long thread. Your not going to "thread" it, just drop it thru. Slap a good thick washer on the bolt, run it thru the helicoil and thru the floor. Another good thick washer and a nylock nut and your good to go. Due to the size of a 12 mm bolt, I'm thinking something like a 3/8 inch grade 5 sae bolt. You should be able to access the thread from under the floor.. You want a bolt that will go thru the seat bracket, the floor, with enough thread to thread the nut on.

 

[ThermionicEmissions]

Thanks for all the info, folks. I didn't realize the size of the torx head dictates the diameter and thread pitch of the bolt, although that makes sense.
The shop matched the heli coil to the original spec, it accepts the original bolt, however the coil looks like it has wormed its way through most of the nut, and it is now only engaged with a few threads.
I'll have them check that, but I've attached some pics.

 

[Curious Hound]

They didn't install that correctly. They were supposed to use a hammer and punch and remove that part that is bent across the hole at the bottom. (The drive tang) have them redo it so you can use the threads.

The torx wrench size does not always designate the thread size. It's just that some of us are familiar enough with these bolts to know what you need. An M12 bolt should not be difficult to find.

 

[Grumpaw]

They didn't install that correctly. They were supposed to use a hammer and punch and remove that part that is bent across the hole at the bottom. (The drive tang) have them redo it so you can use the threads.

The torx wrench size does not always designate the thread size. It's just that some of us are familiar enough with these bolts to know what you need. An M12 bolt should not be difficult to find.

X2...that is a botch job of a helicoil insert. You may be able to salvage it though. from the bottom where the piece of wire is across the thread, try and screw it back up to where it sits flush, and then punch out the horizontal piece of wire.
Looks like the helicoil threads are already rusting....coat the new bolt with a bit of anti seize.

 

[sgtsandman]

If you go the longer bolt and nut route, make sure there is at least 2 threads showing through the nut for proper thread engagement. Most bolts have a bit of a taper to the end of the bolt for easier starting. So, full thread engagement doesn’t happen until about two threads in.

 

[Grumpaw]

If you go the longer bolt and nut route, make sure there is at least 2 threads showing through the nut for proper thread engagement. Most bolts have a bit of a taper to the end of the bolt for easier starting. So, full thread engagement doesn’t happen until about two threads in.

X2, Looking at the pic's a longer bolt/washers/nut would be my first choice. A 12 mm bolt is almost 1/2 inch in diameter (12 1/2 mm is half inch) so using a 3/8 or even 7/16 inch grade 5 bolt/washers/nut would be a simple 10 minute repair job. In fact, since the original hole/threads were enlarged, I'm willing to bet that a simple 1/2 inch bolt would work if you removed the helicoil.

 

[ThermionicEmissions]

They didn't install that correctly. They were supposed to use a hammer and punch and remove that part that is bent across the hole at the bottom. (The drive tang) have them redo it so you can use the threads.

The torx wrench size does not always designate the thread size. It's just that some of us are familiar enough with these bolts to know what you need. An M12 bolt should not be difficult to find.

I knew it! Thanks for the info. Makes sense you'd need to remove the drive tang before installing the nut.

 

[ThermionicEmissions]

X2, Looking at the pic's a longer bolt/washers/nut would be my first choice. A 12 mm bolt is almost 1/2 inch in diameter (12 1/2 mm is half inch) so using a 3/8 or even 7/16 inch grade 5 bolt/washers/nut would be a simple 10 minute repair job. In fact, since the original hole/threads were enlarged, I'm willing to bet that a simple 1/2 inch bolt would work if you removed the helicoil.

Removing the helicoil and going direct to the new threads has occurred to me as well. Certainly seems like the simplest approach. The shop didn't charge much for the helicoil.

 

[ThermionicEmissions]

X2...that is a botch job of a helicoil insert. You may be able to salvage it though. from the bottom where the piece of wire is across the thread, try and screw it back up to where it sits flush, and then punch out the horizontal piece of wire.
Looks like the helicoil threads are already rusting....coat the new bolt with a bit of anti seize.

That's probably a combination of Liquid Wrench and rust from one of the other bolts I worked through there.

 

[Grumpaw]

Long enough 1/2 inch grade 5 bolt, 2 washers, nylock nut shouldn't run more than a few bucks at your local Lowes or Home Depot.

 

[Curious Hound]

Removing the helicoil and going direct to the new threads has occurred to me as well. Certainly seems like the simplest approach. The shop didn't charge much for the helicoil.

The threads you tap for helicoil installation are weird. They do NOT conform to normal bolts.