Arizcowboy
Registered Member
Hey all, I am new to the ColoradoK5 site and just signed up. I am looking to get into a 73-81 or so K5 or GMC Jimmy and thought I would jump into the site here for some suggestions from yall.
I currently own a 1981 GMC K3500 crew cab 4x4. It has a 454 motor with a SM465/NP205 and Dana 60/GM 14bFF 4.56 gears. 6" Tuff Country lift. 35x12.50x16.5 BFG A/T tires. I love this truck! While I do off road it a bit, it is more for my business use and I dont really want to bang it up! So, I am searching for a 4x4 I can have some more fun with! Looking in the 73-81 range. I like this body style and the availability of parts and great aftermarket support. I dont want anything newer. I prefer a short bed truck or a K5/Jimmy. I am leaning toward a full size blazer mostly. I think the K5/Jimmys have a slightly shorter wheelbase yet than a short bed truck. ???
Now, in regards to a K5 or a GMC Jimmy full size... what am I looking for? I need this vehicle for a daily driver. So want something that can be set up for road use with highway friendly gearing. I also want something that I can take for some 'semi serious' off roading. With all that said... what would be the perfect K5/Jimmy to seek out? Now, I know I probably will not find that perfect Blazer and I will have to add some stuff after a purchase... but if I have a choice of blazers, I want to make the right choice.
I am looking at a couple now that have 350 motors, NP205 transfer case and automatic tranny. For off road use, is a manual transmission prefered over an automatic? I like a manual as I feel it gives me more control (not to mention it is more fun to drive!). But is an automatic plenty sufficient for serious off road use? Neither of these blazers I have seen have the full time 4wd and they both have front locking hubs, which is preferable.
Things I would like to consider doing to this blazer after I buy it: add a Dana 60 front diff and a 14bFF rear diff/axle. I would also like to go with lockers, possibly ARB air lockers. Will these 1 ton axles bolt right up to a K5 or are there modifications to do to make them work? I am thinking 35" tires and a 6" lift on this blazer should be plenty. ???
Gearing: I need gears that are good for highway mileage and yet still have some good low range for off road use. I think a 3.73 is rather common in the stock K5's??? That would seem like a good gearing for what I plan to use it for. My big truck has 4.56 gears and I dont drive that thing over 58-60 mph on the highway. I want to be able to drive faster than that with my daily driver on the highway and improve some on gas mileage.
Curious to hear some comments/thoughts on my proposed K5/Jimmy above. Also, anyone from Arizona on here that is selling one?
Thanks
Arizcowboy
I currently own a 1981 GMC K3500 crew cab 4x4. It has a 454 motor with a SM465/NP205 and Dana 60/GM 14bFF 4.56 gears. 6" Tuff Country lift. 35x12.50x16.5 BFG A/T tires. I love this truck! While I do off road it a bit, it is more for my business use and I dont really want to bang it up! So, I am searching for a 4x4 I can have some more fun with! Looking in the 73-81 range. I like this body style and the availability of parts and great aftermarket support. I dont want anything newer. I prefer a short bed truck or a K5/Jimmy. I am leaning toward a full size blazer mostly. I think the K5/Jimmys have a slightly shorter wheelbase yet than a short bed truck. ???
Now, in regards to a K5 or a GMC Jimmy full size... what am I looking for? I need this vehicle for a daily driver. So want something that can be set up for road use with highway friendly gearing. I also want something that I can take for some 'semi serious' off roading. With all that said... what would be the perfect K5/Jimmy to seek out? Now, I know I probably will not find that perfect Blazer and I will have to add some stuff after a purchase... but if I have a choice of blazers, I want to make the right choice.
I am looking at a couple now that have 350 motors, NP205 transfer case and automatic tranny. For off road use, is a manual transmission prefered over an automatic? I like a manual as I feel it gives me more control (not to mention it is more fun to drive!). But is an automatic plenty sufficient for serious off road use? Neither of these blazers I have seen have the full time 4wd and they both have front locking hubs, which is preferable.
Things I would like to consider doing to this blazer after I buy it: add a Dana 60 front diff and a 14bFF rear diff/axle. I would also like to go with lockers, possibly ARB air lockers. Will these 1 ton axles bolt right up to a K5 or are there modifications to do to make them work? I am thinking 35" tires and a 6" lift on this blazer should be plenty. ???
Gearing: I need gears that are good for highway mileage and yet still have some good low range for off road use. I think a 3.73 is rather common in the stock K5's??? That would seem like a good gearing for what I plan to use it for. My big truck has 4.56 gears and I dont drive that thing over 58-60 mph on the highway. I want to be able to drive faster than that with my daily driver on the highway and improve some on gas mileage.
Curious to hear some comments/thoughts on my proposed K5/Jimmy above. Also, anyone from Arizona on here that is selling one?
Thanks
Arizcowboy

) I figured if the truck doesnt need it to run, I dont want it under there. Keep it simple, I always say. So, with that... I like the older rigs. I am fond of the 73-91 body style though. But prefer no newer than 81. I know a carburated engine isnt going to do very good on mileage in these old 4x4's. Just looking to get it as good as I can. I have a 2wd 74' GMC 1/2 ton with a Oldsmobile 455 and it gets right at 11mpg. Not bad really. My big K3500 only gets 6mpg. I would like to improve some on that 11mpg though for my daily driver. I would be happy with say 14mpg in my next truck.