Removable Hardtop Bolts
 

Hello, I have a 1990 Full Size Blazer and need the bolts for the removable hardtop. If there isn't someone that sells these as a kit then what are the size, length(s) and grade for these bolts?

Thanks in advance!

Sincerely,
John McDonnell

Do you have any of the bolts or are you starting from scratch? I'm not sure if anyone reproduces the factory bolts for the top.

You should have six approximately 3" long bolts for around the back of the 1/2 cab and then there will be six shorter bolts for the bed rails, probably 1.5" long. I'm not sure what the thread is exactly, but I'd guess 3/8-16; I doubt they are 1/2-13 or 5/16-18...some trial and error may be necessary if you do not have any of these bolts currently. The original bolts are a fender style bolt with a tapered and threaded tip that aides in getting them started properly, but is not necessary when looking for replacements provided you are careful when starting the bolts and thread them in good by hand before wrenching on them. Most of them are a torx drive with some being safety torx (little pin in the middle of the head); again another unnecessary detail.


If you cannot find originals somewhere (junkyard?), you will likely have to grab some common hex bolts from the hardware store. The topper doesn't really take any load to speak of so grade 5 bolts should be more than ok. Get some good fender washers to spread out the load and you should be good to go.

I believe they are, in fact, 5/16"-18 thread, but no idea on the lengths.

swartlkk, Everything you stated makes sense. I do agree with Tom that they are 5/16-18 vise 3/8ths. I was hoping that someone had their bolts out and/or had that information handy.

Thanks guys for taking the time to reply!

r/
John McDonnell

I had found a few pictures online while putting together my reply and used a visual comparison of those pictures along with a quick glance in the back of my '74 to get to that statement of size. Looking closer at my truck this morning, all of my rail bolts have been changed out to 3/8" washer faced bolts similar to what was used as the factory bolts shown in the thread below and none of the captive cages/plates are there anymore... Should have expected that out of a 44 year old truck.

I did find THIS THREAD over on CK5.com that has a lot of detailed pictures/measurements of the bolts involved that might be of interest to you. It does discuss the 1st gen trucks, but starts off with the OP saying he grabbed bolts from an '82 1/2 top K5 to use in his '71. I hadn't looked at it earlier while I was searching since it mentioned '71 in the thread title, but decided to have a look more recently.

THIS REPLY in that thread details everything about the '82 K5 original bolts. They are 5/16-18 with the upper bolts being 2.5" long and the rail bolts being 1" long.

swartlkk, thanks!

I had seen those pictures but didn't look into more because it was a 20 year older model and that was kind of before the manufacturers started going to smaller fasteners to save money. Not that it helped the cost to the consumer!

Thanks again for the information! I greatly appreciate it!

r/
John McDonnell