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Parts Diagrams?

Hi, I’m wondering if there is a source for part diagrams on the internet. I’m looking specifically for fastener sizes. I’m trying to replace hardware on my truck that’s gone missing. I see some part diagrams on vendor sites but they don’t list fastener sizes and most of it is not in stock anymore to order. It’s a 1995 Chevy S10. …Thanks.

The parts diagrams available on the internet will not show the dimensional characteristics of the parts unless the part has very unique issues, like perhaps being for an antique vehicle. What you can try is going to the part manufacturers’ websites. They MAY have dimensions, depending upon the type of part. Cast, machined, and fabricated parts won’t typically show who actually makes them, but some assemblies might.

Fastener sizes… can you use pin gages, thread gages, and verniers? If so, get both SAE and metric gages, and a digital, dial, or vernier scale caliper (your choice). as a '95 might use a mixture of both. I don’t know how much they’d gone metric in '95. You can measure indexing pin diameters using the calipers and mounting hole center-to-center dimensions using the pin gages too.

Note: Rockler used to sell some great thread gages, in a prickley-block format, in both SAE and metric.

This truck has a mix of metric and standard sizes. I’ll look into the gauges, I wondered how people accomplished this, lol. I’ve just been guessing and going back and forth to the hardware store, which gets a little tedious. Thanks for the response.


Try this website

It’s a little tedious, but they have VERY good parts breakdowns, and have part numbers for the darndest things

And yes, they do list many bolt sizes and thread pitches

Check in your area and you may find a place that sells bolts and nuts by the pound.
We have Farm and fleet, and Fleet Farm in our area and both sell by the pound.
You could buy a mix of 1/4, 5/15 & 3/8 bolts of differing lengths. A hand full of this and a hand full of that. Then you would have a small selection to choose from.

Fine thread SAE and metric you would have to pay for each bolt at the hardware store. But if you bought a few, you could use them to check the missing bolt size and thread pitch and write a list for the next trip past the store.

I wish I could tell you where to buy metric by the pound, but I have not found any place like that around me. That is, where you can just fill a bag and pay by the pound.


Very few of the fasteners on that truck are going to be SAE thread. Virtually the whole truck will be metric save for bolts that go directly into the engine block or heads. And brake caliper mounts and brake lines. But that’s all I can think of.

I’m going insane trying to find this bolt that attaches the transmission brace to the engine.
This is the diagram-
The brace is part #1. I need the bolt #16. I ordered bolt #2, it’s a 9/16.
Bolt #16 isn’t available from GM anymore, I don’t know the part # or the size. I’ve bought every bolt available off the rack in metric and standard sizes, various thread pitches and none of them fit. The 9/16 is just a hair too wide for the engine mount.

Sorry the other link didn’t work

Remove bolt #16 from the bracket on the other side of the engine and match it with a new bolt.

If the bolt heads aren’t rusty you can identify metric bolts by the numeric grade marking, fraction size bolts are marked with lines arranged like spokes.

I don’t have bolts for either side. They disappeared along with the braces after I had the engine replaced. I guess mechanic figured I didn’t need them anymore. I asked if he had any parts left and he said no. I ordered the braces and lower bolts from GM, just stumped by the 2 upper bolts.

It’s difficult to imagine they’d use anything other than a standard size bolt and one of the standard thread pitches. Plus it is sort of hard to imagine they use inch size bolts for your engine. Are you certain about that? guess anything is possible. It’s possible to machine any size bolt with any pitch you want I presume, ifyou have the appropriate machine at your disposal. Which GM does.

hmmm … I had a sort of similar problem I posted here a while ago, for a metric bolt with fine thread pitch, where the bolt had a hole through the shaft; i.e. it wasn’t a bolt so much as a threaded tube. Even with plenty of helpful advice here, and lots of internet searches, I never did find a source for any vendor who offered that item in the length I needed. I solved it using a work-a-round instead… So maybe you’ll have to solve your bolt problem that way too. What if you asked a machine shop to drill that hole out and tap it for a standard size fine pitch bolt?

Before doing that however, make 100% sure you are trying all the standard size bolts, and both of the common thread pitches, in both metric and inch sizes. You don’tr need all the possible lengths, once you determine the size and pitch then you can get the right length. You just need something that matches size and pitch for now. There’s a lot of possible combinations, so it is easy to get confused. In my case above I was also considering pipe thread standards too, which made it even more confusing.

Most hardware stores in my area have a gadget where you can screw a bolt in, or thread a nut on to test it, with all the bolt sizes and thread pitches in both metric and inch size. I’ve found that in-store gadget to be very helpful in situations like this.

The transmission bolts are 9/16, I’m sure of it. I’ve had to take the brace off in the past to change the cooler line. I have to use a wobble socket extension and I hold the bolt in the socket with RTV. I’m pretty sure the upper was 9/16 also because my socket still has the RTV on it. But I can’t thread this 9/16 on at all.

It’s possible the threads are messed up on the mount maybe. Both sides seem the same though. This is a common engine I thought. I guess I could try a salvage yard too. Thanks for the responses. I hate when fasteners disappear, end up spending all this time on a $1.00 bolt.


Why don’t you just head to your local pick a part junkyard to get all those small parts . . . ?!

@db4690 's idea is probably the quickest way to get to a solution. You are right that missing specialty fasteners can turn into a time consuming and frustrating problem. But that’s just the natural order of things I guess when working with mechanical gadgets.

Threads damaged is another possibility. I had to buy some new fastener’s the other day to hold my truck’s air cleaner bracket b/c the old ones threads were damaged. One idea, since you are certain it is 9/16, try a 9/16 tap to clean it out. You’d probably have to have both a course and fine pitch tap, then see which one fits the best.

I believe almost the entire truck is metric

MAYBE some of the threads in the block for accessory mounting brackets are sae, but I doubt it

The OP’s statement above that the bolt is just a little too big for the hole is the same problem I’ve experienced before when I’ve mixed up metric bolts and sae fasteners.

According to my GM parts info (which is not guaranteed), the front brace bolt is a 3/8-16 x 7/8, GM part number 09442119 (or 9442119-some online searches don’t like the leading zero). This appears to still be a good number at the online dealers I checked.
The rear brace bolt is an M10x1.5x32. This seems kind of small considering the OP figures it is around 9/16, unless he’s referring to the bolt head size. The GM part number for that bolt is 15726460. This one appears to have been discontinued by GM.
If the holes/threads in the replacement block are messed up, a tap may be needed to clean them out.

Always amazing. Ask and ye shall receive. Might take a couple days but a lot of answers here.

Thank you! I looked up that part # and just ordered it. Only 75 cents each + shipping, not bad. The hardware store doesn’t carry the 16 thread bolts in this range, so maybe this will do it. I was referring to the head size for 9/16, I didn’t know the actual size, just ordered it from GM. I know it fit in the standard thread in the bolt gauge at the store? Anyway, thanks again.

Head size rarely matters on a bolt. The important part is the thread diameter and pitch, the length and the rating on the bolt (i.e. how strong it is)

You can get confused very quickly if you don’t know what you need… Read this;
It will get you started.

The go to Mcmaster Carr or Fastenal or Grainger and look up screws. They all sell a ton of different screws, nuts and fasteners both metric and English. If you can’t get it from the dealer, look at one of these sites.