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General Site Info => General Discussion => Topic started by: gnx2012 on April 11, 2015, 07:55:41 pm

Title: 1977 gnc sierra
Post by: gnx2012 on April 11, 2015, 07:55:41 pm

Hey all
I bought a 77 GMC sierra 2wd off this elderly man said he was second owner.
I found the original purchase paperwork, RPO code is still intact (glovebox)
How do I check to see if the numbers match? Looks like original 350,4bbl with th400.
Second how can you tell how many times odometer rolled over?

Title: Re: 1977 gnc sierra
Post by: Irish_Alley on April 11, 2015, 11:43:37 pm

whats numbers matching? i dont think theres no way to determine if thats the same motor that came from the factory. but most things will have a series number on them. so you could determine what year the motor is and its factory size and if that matches close to yours then your good. but if your truck is a 77 and the motor is a 76 i would think its the same motor.

the odometer is tricky some say if the numbers dont line up then its been rolled over. best we can do is look at the wear on the brake pedal and the area on the floor below it. my 91 v3500 the odometer said 25,000 which at first with the floor board being worn down below the brake pedal and the numbers not lining it looks like its been rolled over. but the odd part is this odometer has enough numbers to read 999,999.9. so if it was rolled over it would be over a million miles and the floorboard deal you have to look at the history of the truck. it was a airforce truck with a lot of stop and go.

(http://www.crankshaftcoalition.com/wiki/images/thumb/e/e4/S-bbc_block_id.jpg/500px-S-bbc_block_id.jpg)
http://www.crankshaftcoalition.com/wiki/Identifying_Chevy_engines

you can find numbers on the trans also
Partial vin
(http://chevellestuff.net/qd/images/trans/70_arl_vin_stamping.jpg)
might find a plate affixed to the passenger side of the transmission just above the pan rail
(http://chevellestuff.net/qd/images/1967_400_tag.jpg)

http://chevellestuff.net/qd/th400.htm

Title: Re: 1977 gnc sierra
Post by: gnx2012 on April 12, 2015, 06:12:43 am

Thanks this helps a lot. I think I have a 77 with original engine trans and rear with less than a 145,000 all for 1500.00

Title: Re: 1977 gnc sierra
Post by: FlatBlack77 on April 12, 2015, 09:53:52 am

lets see pics of the paperwork! i love seeing that old stuff

welcome by the way and nice buy