thread tap size

[texasfan88]

How do I find the correct thread tap size for a factory 13mm bolt hole? I have a 2018 ram 1500 and I've been trying to install this S&B cold air intake. The problem is that the 13mm bolt that connects to the bracket on the air box and then bolts into the fender well will not fully tighten because the bolt hole is stripped. As a matter of fact, if I try to use a ratchet to tighten it, the bolt actually gets looser. I really want to avoid spending a couple hundred bucks on a full tap and die set, especially since I won't be using 99% of the parts and since you can get individual taps on Amazon, I was wondering if anyone knew the correct size to get. I assume since it's a 13mm hole that I would need a 13mm tap but as far as the pitch goes, that part I'm not sure of.

 

[Bob Macknight]

on the chart in my set it shows m14x1.25 or 9/16-18 if you get a hold of a set from auto parts store they should be able to concur

 

[Daw14]

Might not be the most correct way but you could go up till the next size with a self tapping bolt . Your local hardware store should have a good selection. I ran into similar issues installing my volant intake ,but was able to proceed after visit to hardware store.

 

[texasfan88]

Thanks for the responses. This one bolt I'm dealing with is ******* me off. I keep trying to readjust stuff, tighten things down, etc. but the intake keeps rattling whenever I drive. Also, the instructions for that bracket aren't very consistent either. One set of instructions says to use the 13mm bolt and flat washer that came in the kit, while others say to reuse the factory 13mm bolt. I used the new one and was able to get it fully tightened, however I took it off because the vibrations from my exhaust system were causing this annoying metal on metal vibration so I decided to go with the factory bolt. Well apparently, I may have over-tightened the previous bolt because although I can get it pretty tight by hand, if I try to fully tighten it with a ratchet, it starts stripping that thread hole out. I have a Lowes and a Home Depot near me, so I'll swing by there and see if they can help me out. I'll even bring an extra bolt I have that is identical to what I'm using, so that should help me out.

 

[caulk04]

Instructions often refer to bolts by their hex size which is incorrect. A bolt with a 13mm hex is likely a 10mm thread which is likely to be a 10x1.5 thread.

If the hole is stripped, a tap isn't going to help. You could probably get away with bumping up from a 10mm thread to a 7/16" sae thread.

 

[hunterdan]

Take the bolt to a hardware store, they usually have a thread chart there you can thread the bolt in to verify thread. Probably m8x1.5 thread though if it uses a 13mm wrench.

 

[Fast69Mopar]

How do I find the correct thread tap size for a factory 13mm bolt hole? I have a 2018 ram 1500 and I've been trying to install this S&B cold air intake. The problem is that the 13mm bolt that connects to the bracket on the air box and then bolts into the fender well will not fully tighten because the bolt hole is stripped. As a matter of fact, if I try to use a ratchet to tighten it, the bolt actually gets looser. I really want to avoid spending a couple hundred bucks on a full tap and die set, especially since I won't be using 99% of the parts and since you can get individual taps on Amazon, I was wondering if anyone knew the correct size to get. I assume since it's a 13mm hole that I would need a 13mm tap but as far as the pitch goes, that part I'm not sure of.

I'm betting that you do not have a 13mm bolt holes and threads. It's probably a 13mm hex head bolt and the thread size is M8x1.25.

You can purchase a helicoil kit from the local Auto Parts that comes with the helicoils, a tap and a single drill.

 

[texasfan88]

I'm betting that you do not have a 13mm bolt holes and threads. It's probably a 13mm hex head bolt and the thread size is M8x1.25.

You can purchase a helicoil kit from the local Auto Parts that comes with the helicoils, a tap and a single drill.

Exactly, the head is 13mm but the shank diameter is probably 8-10 mm. Kind of makes things confusing because the instructions for the air intake I’m struggling with refers to the size of the bolts as the size of the head, so if it says 13mm or 1/2 inch, that’s the size of socket you would use. However, and I made the mistake of not bringing the bolt with me to compare, but if you look for a 13mm bolt at the hardware store, they’re referring to the size of the bolt shaft, whereas the head is probably 3/4 inch. I tried some of this loctite thread repair system and it didn’t work at all, so I’m going to try to find a tap that’s the correct size. I’ll get it fixed one way or another. I’m not going to let one bolt ruin this for me.

 

[Fast69Mopar]

Exactly, the head is 13mm but the shank diameter is probably 8-10 mm. Kind of makes things confusing because the instructions for the air intake I’m struggling with refers to the size of the bolts as the size of the head, so if it says 13mm or 1/2 inch, that’s the size of socket you would use. However, and I made the mistake of not bringing the bolt with me to compare, but if you look for a 13mm bolt at the hardware store, they’re referring to the size of the bolt shaft, whereas the head is probably 3/4 inch. I tried some of this loctite thread repair system and it didn’t work at all, so I’m going to try to find a tap that’s the correct size. I’ll get it fixed one way or another. I’m not going to let one bolt ruin this for me.

Hit the local Auto Parts store and get a helicoil kit for M8x1.25 and if it does not come with a drill bit then pick up a 17/64" drill bit and be done.

Drill it straight, run the tap in to cut the threads, install the helicoil and then your bolt. Good luck with the repair!

 

[GTyankee]

Many hardware stores have coated cardboard cards
Some have bolt cards, tap size cards, etc.
You have to ask for them, they disappear if they are on the counter top

 

[texasfan88]

Well, I came up with a very simple yet effective solution and that is to simply not use the bracket at all. Again, this is regarding the S&B cold air intake system for the 09-18 ram 1500 trucks and as I'm sure most of you probably know, there's a bolt that goes through the top portion of the air box, through a rubber grommet and through the fender. There are two bolts that go through the bottom of the air box and through the fender liner and then finally, there's a bracket that bolts to the bottom of the air box and then bolts through the bottom part of the fender. Well apparently, if you take the bolt that's supposed to go with that bottom bracket and then use that for the bolt that goes through the side of the fender at the top portion of the air box and then those two smaller bolts that go through the fender liner, there actually isn't any need whatsoever for that bottom bracket. There literally isn't anywhere for it to go because you have two bolts, holding to the fender liner which itself is held on by a number of screws and clips and then one large bolt attaching it to the fender. Should've thought about that before I started messing with it lol but regardless, the air box does not move at all and best of all, no loud rattling noise anymore. I finally get to actually enjoy my new air intake.