What's new
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

new to 4x4

N

newlyblzed

1/2 ton status
Joined
Sep 21, 2007
Posts
290
Reaction score
0
Location
Klamath Falls, Oregon
hello guys. My name is Brian, brand new to the site and I just recently bought my first off road rig. I bought a 1980 k5 blazer off a friend for pretty cheap. It is a little sluggish though and I want to start upgrading it. it runs a 350 that sounds great with 109000 miles or so. it has a lift but I don't know how big and runs 35 rubber. The 350 has a hard time pushing it but I don't think it is the engine..I think it is in the gearing. Running in 4 low the truck jumps and scoots but in 4 hi or 2wd it has a hard time climbing even the small hills. I already went throuhg and did a tune up (compression at every cylinder was 150 +/- 5 psi) and am in the proccess of rebuilding or replacing the carb. Engine work is my cup of tea...I don't know anything about the rear end and gears, how do I tell whats in it and what do I want to switch to for improved torque?
thanks
 
the search on here is full of the answers to your questions tells you how to spin your wheel and figure your gears or you could pull the cover off. i would assume that it is stock gears. you could take some pics of your truck (ie springs front and rear and side views) and we could probly give you a good idea of what lift height it is. oh welcome to the site btw i used to live in woodburn Or. damn i miss that place
 
welcome to the greatest site on earth :D , I have been addicted from day 1. I come here every single day unless Im on travel for work. this site is a wealth of info. you can restore to stock or build a full tilt rock crawling monster with the help of this site. what you do with your imagination is up to you. post up some pics for sure. there are good people here. I have met and wheeled with some cool, really good guys. good luck on your build.
 
these trucks can handle pretty big tires with no lift. i'm running 33x12.5 at stock height with no rub offroad. yours might have as little as a 2.5" lift and be fine.

as far as your gears go, i've seen stockers running 3.08s. i think mine may be one of them, but i was in a hurry when i changed gear oil about a year ago and forgot to count my teeth :doah:. i'll do it the lazy way: jack up rear end, spin tire, and count how many times the d-shaft rotates. good way to estimate.
 
here are some pics...I have been on here for about two hours now reading everyones posts...I am amazed at how much stuff..not to mention the quality...is on here...anyway here are pics

DSCN4678.JPG

DSCN4768.JPG

DSCN4776.JPG

DSCN4770.JPG

DSCN4777.JPG
 
i took off through a open field chasing a bunny goofin off with my gf and didn't see this rock (pic of rock outside of door) jumped the truck a good deal and threw her and me around a little...but didn't so much as bottom out my suspension!! or pop the tire!!
 
welcome.


to find out your gears I would recomend pulling the cover. this serves two purposes. you know exactly what you are dealing with and you get to inspect the bearings and change the oil. for all you know it could be original to the truck.


from the pics I would geustimate a 4-6 inch lift. does it have blocks in the rear? measure them. that should clue you in. if you are anything like the majority of the wheelers on here it will not matter though because you will have an entirely different suspension under there eventually.:D
 
I was thinkin 6" the blocks look to be about that but I haven't actually measured..and your right...eventually the whole truck will be different!! Still in the planning stage though...don't know exactly where I am going with it...first of all though I need to find where I am losing my power because the thing is gutless..and it is hard to go wheelin when you can't climb up anything!!
 
I say look asap I had 2.73 under my truck and didn't know it because my Engine was strong. Then instead of just changing gears I went and got a set of 3/4 ton axles with the gears I wanted. After that nothing could stop me from going where I wanted to go except the law:D
 
35s with stock high gearing will slow you down for sure. You need at least 4.10s really. Looks like about 4" lift to me.
Truck looks in good shape too. Good luck and welcome!
 
Truck does indeed look in good shape!

Stock gears are probably 3.73, but could be almost anything. I agree that popping the cover and changing the fluid is a good idea, but if you want to know the gearing quickly so you can "web build" the rig on here and while daydreaming at work, just put a mark on the rear drive line, jack up the rear axle and rotate a rear tire 1 full revolution, counting the number of revolutions the drive shaft makes... including aproximate fractions. 3 3/4 turns of the driveline = 3.73, about 4 turns = 4.10, etc.
 
newlyblzed said:
hello guys. My name is Brian, brand new to the site and I just recently bought my first off road rig. I bought a 1980 k5 blazer off a friend for pretty cheap. It is a little sluggish though and I want to start upgrading it. it runs a 350 that sounds great with 109000 miles or so. it has a lift but I don't know how big and runs 35 rubber. The 350 has a hard time pushing it but I don't think it is the engine..I think it is in the gearing. Running in 4 low the truck jumps and scoots but in 4 hi or 2wd it has a hard time climbing even the small hills. I already went throuhg and did a tune up (compression at every cylinder was 150 +/- 5 psi) and am in the proccess of rebuilding or replacing the carb. Engine work is my cup of tea...I don't know anything about the rear end and gears, how do I tell whats in it and what do I want to switch to for improved torque?
thanks
Click to expand...


Welcome to the jungle :D !!

Why not swap in an RV cam if you want more torque? Followed by a set of headers.
 
That vintage is more than likely one of the many that got 3.08's or 2.73's. You want at least 4.10's in there with 35's. 4.56's would be better, but with no overdrive it'd be buzzing pretty high on the highway.

no need to count teeth, just yank the cover off, blast the crud out with brake Kleen and read the numbers stamped on the edge of the ring gear. The numbers are always some part number crap, then pinion, ring gear, and date code.

XXXXXXXXX 10 41 12 79

10= pinion
41= ring gear
12= December
79= 1979

Rene
 
looks nice and clean! Good buy.
I'd agree with Rene on the gearing. Mostly like what gearing it has I doubt it is low enough for the 35s. I'd invest in a 14ff rear and 3/4ton front with 4.10s or 4.56s if you want to do more wheeling.
 
eveyone keeps saying it was a good buy. I thought it was a steal..I actually felt bad because we are friends. I paid the guy 1700 (actually 500 down 200 a month) for the truck. Like I said engine is strong interior is immacualte, minor oil leaks out of the engine and trans but nothin serious. front hubs work great, driveline is only 4 mos old. He just had an used tranni put in which scares me but dollars for dollars who cares right?

So I already have my DD, I want this Truck to be my hunting rig and go wherever I want rig...I probably won't ever do any serious rock climbing but definately some mudding in it's future. what do I need to jump to the 4.56 gearing? Thinking that biggest is always best right?!? With that gearing will the TH350 run on the freeway or will it be rapped out? I don't want to go to cazy and not be able to drive my truck to the woods. I hear a lot of talk about getting the 3/4 ton axles. is that usually cheaper than just replacing the gearing...oh and my rear end is a 12 bolt cover will tear it apart tommorrow or sunday to look at the gears

getting long winded thanks everyone
 
newlyblzed said:
eveyone keeps saying it was a good buy. I thought it was a steal..I actually felt bad because we are friends. I paid the guy 1700 (actually 500 down 200 a month) for the truck. Like I said engine is strong interior is immacualte, minor oil leaks out of the engine and trans but nothin serious. front hubs work great, driveline is only 4 mos old. He just had an used tranni put in which scares me but dollars for dollars who cares right?

So I already have my DD, I want this Truck to be my hunting rig and go wherever I want rig...I probably won't ever do any serious rock climbing but definately some mudding in it's future. what do I need to jump to the 4.56 gearing? Thinking that biggest is always best right?!? With that gearing will the TH350 run on the freeway or will it be rapped out? I don't want to go to cazy and not be able to drive my truck to the woods. I hear a lot of talk about getting the 3/4 ton axles. is that usually cheaper than just replacing the gearing...oh and my rear end is a 12 bolt cover will tear it apart tommorrow or sunday to look at the gears

getting long winded thanks everyone
Click to expand...



with 35's it should not be bad at all as far as rpm goes. your way tall now so its actually just correcting it, and giving you a little extra torque thru the gears. with 4:88's you would be running more rpm then you probably would want. me personally, I would run the 4:88's cause of the offroad ability advantage, but you would sacrifise fuel economy. just does not sound like what you want. 35's W/4:56's are fine.

My burb has a 700r so I will be running 4:88's. overdrive makes the difference ofcourse. The 14FF swap is an easy swap to do. do you need it, probably not, BUT 35's are max for your axles, actually 33's would be better, and with mudding your going to stress those axles for sure. if your just trolling thru a few mud puddles, your fine. there are things you can do to strenghten a 12 bolt, axle shafts, truss, what not. again, me personally, I would do a 14FF swap in a heart beat just because its easy and I dig doing that kind of thing.

if you break that axle you will know you need to do a swap, hopefully you can get it back home to do it it then.
 
newlyblzed said:
what do I need to jump to the 4.56 gearing? Thinking that biggest is always best right?!? I hear a lot of talk about getting the 3/4 ton axles. is that usually cheaper than just replacing the gearing...
Click to expand...

if you find a set of 3/4 ton axles with the gears you want it is a lot cheaper then regearing what you have and you will get a stronger rear end. In my area a matching set of 3/4 ton axles goes for about $300. you will spend probably that much replacing all the brake components, but you can't get gears set up professionally for that cheap.
 
your cheapest route and easiest to find would be a d44 and 14ff out of an old K20. Most common were 4.10s in them, but some had 4.56s. For what you said you want to do, 4.10s would even work fine with non aggressive 35s and some light mudding. I had a 77 K20 with 4.10s and some 36s with a 305 sbc and it worked fine, 4.56s would have been nice but more expensive.
 
there is a guy on here from seattle sellin a 14bff with 4.10 for 200. Think I'll get it and wait on the 4.56 or 4.88 until later. little further down the road maybe when it is a true off roader..right now I need to get the gearing fixed so that it is practical. The gearing now is killing me...I could run a faster 1/4 mile!! gonna search the forum for a swap write up to see what all I'll need.
 
You must log in or register to reply here.

Latest Posts

Top Bottom