Big Hump or Little - How to Tell the Difference - The 1947 - Present Chevrolet & GMC Truck Message Board Network

srvivor71 · 08-07-2011, 05:34 PM

I'm getting ready to order a new floor mat for my 71 GMC. It's a 350 with a 350 TH trans and a NP 205 transfer case. With that info, does anyone know if I have the big hump or the little? If not, how can I tell for myself?

**leddzepp** · 08-07-2011, 05:42 PM

4 x 4 should have the high hump. Easy way to tell is that it bolts in. Small humps are welded in.

67c10rustbuket · 08-07-2011, 06:04 PM

A small hump floor is one as stamped piece, on a high hump floor the high hump part itself is bolted in to the floor.
lmc says the low is 4" tall and the high is 6" but the are not any sharp bends to measure off of so its not a good way to find out. also they say 4x4 and/or floor shift equipped trucks had the high hump. but thats not always true since GM liked to change things up just to confuse us 40 years later.
personally i would climb underneath and look or yank the carpet and take a look. search this site for high hump and you should find plenty of pics so you'll know what your looking for.

srvivor71 · 08-07-2011, 08:03 PM

Thanks for the help guys! Like you said, I searched the site for high hump and saw lots of pics. I pulled up my old mat and see that it is bolted down - hi hump. I'll be ordering my new mat soon. Thanks again!

08-07-2011, 05:34 PM	#1
srvivor71 Registered User Join Date: Sep 2010 Location: Sullivan County, NY Posts: 455	Big Hump or Little - How to Tell the Difference I'm getting ready to order a new floor mat for my 71 GMC. It's a 350 with a 350 TH trans and a NP 205 transfer case. With that info, does anyone know if I have the big hump or the little? If not, how can I tell for myself?

08-07-2011, 05:42 PM	#2
leddzepp Moderator Join Date: May 2007 Location: Southern Cal Posts: 19,995	Re: Big Hump or Little - How to Tell the Difference 4 x 4 should have the high hump. Easy way to tell is that it bolts in. Small humps are welded in. __________________ 1972 C/10 Cheyenne Super SWB. Restored, loaded, slammed. 1968 C/10 50th Anniversary LWB. Unrestored, stock, daily driver/work truck. RIP ElJay RIP 67ChevyRedneck RIP Grumpy Old Man

08-07-2011, 06:04 PM	#3
67c10rustbuket Registered User Join Date: Apr 2011 Location: Mustang, Oklahoma Posts: 2,806	Re: Big Hump or Little - How to Tell the Difference A small hump floor is one as stamped piece, on a high hump floor the high hump part itself is bolted in to the floor. lmc says the low is 4" tall and the high is 6" but the are not any sharp bends to measure off of so its not a good way to find out. also they say 4x4 and/or floor shift equipped trucks had the high hump. but thats not always true since GM liked to change things up just to confuse us 40 years later. personally i would climb underneath and look or yank the carpet and take a look. search this site for high hump and you should find plenty of pics so you'll know what your looking for. __________________ Dan <---(my name) 67 SWB C10 project "GEORGIA"-59 Brookwood 2dr wag...Next project-03 Tahoe 4x4 5.3 family ride-07 Hondur Accord, commuter car

08-07-2011, 08:03 PM	#4
srvivor71 Registered User Join Date: Sep 2010 Location: Sullivan County, NY Posts: 455	Re: Big Hump or Little - How to Tell the Difference Thanks for the help guys! Like you said, I searched the site for high hump and saw lots of pics. I pulled up my old mat and see that it is bolted down - hi hump. I'll be ordering my new mat soon. Thanks again!



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.