2nd Gen Non-Engine/Transmission Fuel Tank Strap Bolt Stripped

[Dave M]

A while back I was removing my fuel tank (97 3500 dually LB 4x4) to replace the sending unit. One of the fuel tank strap nuts would not tighten up but would feel like it was loose on the bolt after it was a few threads tight. I swapped nuts and it appears I have bad threads on this one stud/bolt. Anyone know if this bolt/stud can be removed or have any suggestions on how to repair this.



I finally got my goosenck ball... which had stripped threads... out of my bed so I can now remove my bed to repair this problem. I have not removed the bed yet but figure if I need to remove the bed or jack it up a little to get to this stud. Can I replace or repair this stud?



Thanks for any info or ideas.



Dave

 

[ata]

I think what I would do is get some pipe or heavy tubing about 1 to 1 1/2 inches long that just fits over the bolt and slide it on and then the nut and a washer. That way you would move the nut down to where the threads are good.

 

[Dave M]

I think what I would do is get some pipe or heavy tubing about 1 to 1 1/2 inches long that just fits over the bolt and slide it on and then the nut and a washer. That way you would move the nut down to where the threads are good.

That might work if I have enough thread. I can't remember how much was good. I'll have to add some washers and try it. I just hate to have it fail and my tank fall and cause an accident.

 

[kenny61]

You can run a die or a thread repair die up and down it and hope it isnt too damaged to recut the threads you just got to figure out what the thread pitch is

 

[Joseph Donnelly]

I doubt there are enough of the threads left to tap and reuse the stock stud, which should be M10 x 1. 5 thread. I would knock the spot welded bolt out (that's what the stud really is), and replace it with a new bolt with a plate/strap welded to the head so it will quit turning when the strap hits the side of the crossmember. I had a bad fuel tank mounting stud on my 97, but in my case the spot weld had broken.

 

[Dave M]

I doubt there are enough of the threads left to tap and reuse the stock stud, which should be M10 x 1. 5 thread. I would knock the spot welded bolt out (that’s what the stud really is), and replace it with a new bolt with a plate/strap welded to the head so it will quit turning when the strap hits the side of the crossmember. I had a bad fuel tank mounting stud on my 97, but in my case the spot weld had broken.

Good info. Can I get this stud from the dealer (I'll check next week) and do I need to spot weld it back in place?

 

[Joseph Donnelly]

It would be very difficult to put in a new bolt and weld it into place with the bed on the truck. It is a lot easier to simply buy a long, fully-threaded bolt of good grade (grade 5 or 8 if you get 3/8 x 16; grade 8. 8 or 10. 9 if you go with the original metric threads). Weld a steel plate/strap to the head, or use a thick strap and tap it, red loctite the bolt to it after threading the bolt through the strap all the way to the head. Then, when it turns upon tightening the nut, the strap will stop against the wall of the cross member.

 

[Dave M]

It would be very difficult to put in a new bolt and weld it into place with the bed on the truck. It is a lot easier to simply buy a long, fully-threaded bolt of good grade (grade 5 or 8 if you get 3/8 x 16; grade 8. 8 or 10. 9 if you go with the original metric threads). Weld a steel plate/strap to the head, or use a thick strap and tap it, red loctite the bolt to it after threading the bolt through the strap all the way to the head. Then, when it turns upon tightening the nut, the strap will stop against the wall of the cross member.

Good idea. I haven't tried getting in there again to see how to get the bolt out, but it probably requires removing the bed. I remember there was very little clearance between the tank and frame and it was a long reach up from below with very little wiggle room. It's either drop the tank and hope I can get to the bolt without messsing with the bed or (more than likely) I'll need to lift the bed to get to the bolt.



Thanks for the ideas.



Dave

 

[Joseph Donnelly]

There's enough clearance between the cross member and the bed to remove the old bolt and get a new one with a strap on it into the cross member.

 

[Dave M]

There's enough clearance between the cross member and the bed to remove the old bolt and get a new one with a strap on it into the cross member.

Thanks for the heads-up Joe. I may try it end of this week. I called dealer today and they do not list that bolt/stud so I'll have to figure out a bolt or maybe use all thread and double nut it on the frame end.



If I can get in there without lifting the bed I'll take a look but I may have trouble removing the old stud if its welded in. I may try dropping the tank and cutting off the first 3-5 threads and see if there is enough good thread left to get a nut on.



I'll update with pics when I look at it probably either this Friday or Sat.



Dave

 

[Dave M]

I fixed my stripped fuel tank bolts. I used a thread die to re-tap the threads. The thread was metric M10X1. 5 just as Joe Donnely suggested. The bolts were 1 1/2 inch long and the first 3 threads were cross threaded and the nut stopped there, so I had over 1 inch of good thread to tap once I got past the stripped threads.



I had to use a standard 3/8X16 NC die to tap the first 3 threads and then followed it with the metric die because the metric die would not start it.



The 1st pic shows the side of truck and the front and rear tank strap can be seen wrapped around the tank. The stripped bolt was actually under the cab and to remove it would have required pulling the cab or drilling thru the cab from inside to get clearance for the bolt to be removed. There was less than an inch clearance between bottom of cab and top of bolt of this bolt under the cab. The rear strap bolt was under the bed and had plenty of clearance to reove it.



The 2nd pic shows the driveshaft carrier bearing and the strap bolt/nut up inside of the carrier bracket. The bad nut is hidden in the dark shadow of the carrier bearing. I had to drop the driveshaft carrier bracket and carrier bearing support to get to the bolt/nut.



The 3rd pic is the rear strap bolt that was good and is located under the bed. There was plenty of room above the bolt to remove it without pulling the bed but this was the good bolt.



The 4th pic shows the carrier bearing installed. Follow the red strap up and you will see where the bolt/nut that is stripped is.



The 5th pic was taken of the good rear bolt using a mirror to look down on the head of the bolt. The bolt head is black with a rounded head and a recessed hole in the center of the head. I don't know how this bolt was originally installed. The bolt looks like part of the cross member since the bolt head and cross member were both painted black. The bolt head could have an allen head but I could not tell. I don't know if its spot welded in or screwed in like a sheet metal screw.

 

[Dave M]

More pics of the repair. The 1st pic shows the carrier bearing bracket disconnected from frame and the bracket rotated down tward ground. You can see the stripped bolt in the middle of the 2 carrier supprt bolts and the tank strap below it. I used the red straps around the tank in case the bolt failed so the strap would support the tank.



The 2nd pic to the right shows a close up of the bad bolt with stripped threads in between the 2 carrier bracket bolts.



The 3rd pic shows the M10X1. 5 die on the stripped bolt ready to tap.



The 4th pic shows the completed repair on the stripped bolt installed in-between the carrier bracket. It's fixed.

 

[Dave M]

More pics of re-tapping with the die and the completed job. I re-tapped both bolts.