What size bolts do you use in your Blazer top? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

**BAD4X4** · 10-28-2007, 11:11 PM

Question for all you blazer guys. I got a new top for my blazer and was wondering what size bolts typically go in these. My old blazer top used fine thread 3/8 and the new top looks to be a 5/16 course thread, but don't screw in real easily??? Any help or suggestions would be greatly appreciated...

Thanks
Dana

Old Chevy Mech · 10-29-2007, 12:27 AM

My 70 has the 3/8" SAE thread. Whatever you do IMHO make sure you put antiseize on them before installing!

Frank

**truckster** · 10-29-2007, 01:00 PM

Looks like mine (72) are 5/16 coarse. I'd recommend you use flat washers under the heads of the bolts to protect the fiberglass.

BobbyK · 10-30-2007, 10:32 AM

Here are the bolts used for my 71,single walled top.

I used stainless fasteners for the bedrail.

Livrat · 01-20-2009, 12:05 PM

All of my Blazers have hex head 5/16 coarse thread bolts, they look almost like a fender bolt but have a flanged head.. (built in washer)

Longhorn Man · 01-20-2009, 06:26 PM

slightly off topic, the single wall tops, where the bolts go down, is the bed side threaded?
This will be marked for FAQ.

Old Chevy Mech · 01-20-2009, 06:39 PM

My Parts Blazer is a 72 single wall and no the bed is not. Nuts & washers are used.

BobbyK · 01-20-2009, 10:45 PM

My bedrail is threaded.
Is it factory?...who knows.
I blew up the pic so you could see that every other hole is threaded.

jaros44sr · 01-23-2009, 10:30 AM

My '72 has both holes, single and double. The ones that bolt from the top are attached with nut plates that can slide a little for adjustment

10-28-2007, 11:11 PM	#1
BAD4X4 Senior Member Join Date: Jan 2003 Location: La pine Oregon Posts: 1,668	What size bolts do you use in your Blazer top? Question for all you blazer guys. I got a new top for my blazer and was wondering what size bolts typically go in these. My old blazer top used fine thread 3/8 and the new top looks to be a 5/16 course thread, but don't screw in real easily??? Any help or suggestions would be greatly appreciated... Thanks Dana __________________ 1972 Cheyenne K-30 6"lift {502 PROJECT} 1972 Cheyenne K-30 8"lift 454 450hp {Ol'Blue} 1972 Cheyenne K-20 Custom Stretch 6" lift 454 1972 Custom Deluxe K-20 4" lift 2007 GMC Crew Cab Diesel 6"lift {The Tow Rig 2017 Ford F-350 Crew Cab 6.7 6"lift (Wife's) 1977 El Camino SS Grandpa baught new 1986 K-30 Crew Cab 502 1955 Chevy 2-Door gasser 454 550hp{project} 1956 Chevy Bel-Air 2-Door hardtop 572 700hp 1979 Ford F-350 All Original 4x4 (Wife's)

10-29-2007, 12:27 AM	#2
Old Chevy Mech Keepin it runnin! Join Date: Oct 2007 Location: Deep River, CT Posts: 1,036	Re: What size bolts do you use in your Blazer top? My 70 has the 3/8" SAE thread. Whatever you do IMHO make sure you put antiseize on them before installing! Frank __________________ 1970 K-5 4X4 Blazer 1970 K-20 4X4 Long Bed "Liberty Means Responsibility, that is why most men dread it"

10-29-2007, 01:00 PM	#3
truckster Senior Member Join Date: Jan 2001 Location: Orem, Utah Posts: 7,791	Re: What size bolts do you use in your Blazer top? Looks like mine (72) are 5/16 coarse. I'd recommend you use flat washers under the heads of the bolts to protect the fiberglass.

10-30-2007, 10:32 AM	#4
BobbyK Registered User Join Date: May 2000 Location: Petrolia,Ontario,Canada but working in Port Huron,Mi. Posts: 1,769	Re: What size bolts do you use in your Blazer top? Here are the bolts used for my 71,single walled top. I used stainless fasteners for the bedrail. __________________ 71 blazer,350SBC,approx.375HP,700R4,factory GM TPI.Dual electric fans,33x12.5x15 ATR on stock suspension. Petrolia,Ontario,Canada but working in Port Huron,MI. See ALL my Blazer pic's HERE Last edited by augie; 04-09-2011 at 03:11 PM.

01-20-2009, 12:05 PM	#5
Livrat Member #1049 Join Date: Jun 2000 Location: Troy Montana Posts: 3,940	Re: What size bolts do you use in your Blazer top? All of my Blazers have hex head 5/16 coarse thread bolts, they look almost like a fender bolt but have a flanged head.. (built in washer)

01-20-2009, 06:26 PM	#6
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,693	Re: What size bolts do you use in your Blazer top? slightly off topic, the single wall tops, where the bolts go down, is the bed side threaded? This will be marked for FAQ.

01-20-2009, 06:39 PM	#7
Old Chevy Mech Keepin it runnin! Join Date: Oct 2007 Location: Deep River, CT Posts: 1,036	Re: What size bolts do you use in your Blazer top? My Parts Blazer is a 72 single wall and no the bed is not. Nuts & washers are used. __________________ 1970 K-5 4X4 Blazer 1970 K-20 4X4 Long Bed "Liberty Means Responsibility, that is why most men dread it"

01-20-2009, 10:45 PM	#8
BobbyK Registered User Join Date: May 2000 Location: Petrolia,Ontario,Canada but working in Port Huron,Mi. Posts: 1,769	Re: What size bolts do you use in your Blazer top? My bedrail is threaded. Is it factory?...who knows. I blew up the pic so you could see that every other hole is threaded. __________________ 71 blazer,350SBC,approx.375HP,700R4,factory GM TPI.Dual electric fans,33x12.5x15 ATR on stock suspension. Petrolia,Ontario,Canada but working in Port Huron,MI. See ALL my Blazer pic's HERE

01-23-2009, 10:30 AM	#9
jaros44sr Registered User Join Date: May 2006 Location: Philadelphia, Pa. 19454 Posts: 9,421	Re: What size bolts do you use in your Blazer top? My '72 has both holes, single and double. The ones that bolt from the top are attached with nut plates that can slide a little for adjustment __________________ Semper Fi...Uncle Sam, you da man All parts offered to help are free, unless otherwise noted Dont try this stuff in my build thread, unless you have 55 years of mechanical OTJ training SAFETY FIRST AS usual, off topic They say your mind goes second, can't remember the first Jim



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