GM Truck Club Forum banner

New member intro and pre-purchase question

1369 Views 13 Replies 10 Participants Last post by  canislupis69
Hi forum members! Hello from Seattle.

I'm new to this forum but not new to automotive forums in general. Anyway I've been looking for a good weekend work truck for a while now, and I've found a good candidate, thought I'd check with y'all and see if you have any insight about this truck. I found it on Craigslist (!), the owner has had it for about 4 years and used to be a transmission mechanic. He has about 4 other trucks scattered around his yard but claimed this was his daily driver, and when he came home from work today to meet me, he was driving it.

It's a 1977 K20 with a small block 400 and the TH350. It is almost completely stock. Cheap white steel wheels, non-matching GMC tailgate, aftermarket headers, and a funky dual exhaust that puts the tailpipes between the doors and rear wheels on each side. Other than that it's very stock. It's not too pretty, there are some dents here and there and most of the trim is gone, but the paint isn't bad overall, very little rust, and the interior is pretty clean. No holes in the original seats, glass is all good, everything works. Full-time 4wd. The engine bay is nice and neat, and other than the headers and a new battery, very stock as well. There is a lot of grease on the valve covers and block but nothing you wouldn't expect from an old truck. Starts right up, drives good, shifts smooth, brakes are okay, the seller is offering to put in a new master cylinder for me.

Is there anything specific I should look for that might be trouble later on? I looked over the truck pretty well and saw nothing out of the ordinary. Compared to a 1983 K5 I owned, the truck seems to be unmolested and ready to work. Any tips, warnings, or encouragement you guys can offer will be greatly appreciated. Thanks in advance!

Seller is asking $1400.
See less See more
1 - 1 of 14 Posts
Welcome to the club Dasch. My Dad had a few trucks of that vintage. No real problems except the normal stuff you will see with any truck of that age whether it's Chevy, Ford or Dodge. One foible with all of the older small block Chevys is the rear main crank seals always leaked. They are 2 piece seals & they all leaked right up untill Chevy redesigned them & used a 1 piece seal. Not really a big problem unless they were really shot & just poured the oil out all over the clutch plate & then the clutch would end up slipping.
The only other thing I can think of is the 400 C.I. motors had siamesed cylinders on #3 & 5 & #4 & 6. This didn't allow any coolant to flow between them for cooling. This required top notch cooling system maintanance to keep them from having overheating problems. Make sure the engine temperature guage in this truck is working, & when you drive it make sure you get it completely warmed up & watch & see what the temp guage does. Take it up a couple of steep grades & see how high the guage goes. If it all seems normal then this isn't an issue with it.
Listen for abnormal noises & vibrations on your test drive. Listen for any unusual engine noise, rear end howl, wheel bearing noise, trans noise & or any vibrations that shouldn't be there. Basically look for the same problems you'd look for in a car that shouldn't be there.
See less See more
1 - 1 of 14 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.