81 k5 BAD SHAKE AT 50+

[Kaiser85]

Ok so heres the story- i bought an 81 k5 for 1800. It has a built 350, and a body lift, 315/75-16 cooper discovery SST tires. The TH350 was slipping so i had a hot shot driver pick it up and trailer it to the trans shop for a full overhaul. When the PO was loading it he couldnt hardly.get it up the ramps..... for WHATEVER REASON,this idiot thought itd help if he put in 4l. He tried to drive up the ramps onto the goose neck, and i heard a pretty loud clunk. He backed up, put it in 2h and got a run this time. The shop rebuilt the trans and today i picked itup. The owner of the shop said it had a really back shake at 50 . And it did. He said he thought the tires needed to be balanced so i drove it to thebtire shop and had them balanced... they were off, and it helped.... SOME. while at the tire shop a guy pointed out my transfer case was leaking, and sure enough there was about a 5" puddle of fluid under. Its leaking from the case halves.

The PO swears it never shook. He has no reason to lie to me at this point. Im a very easy going guy and all. What do you guys think? I mean, could it be a vibrating drive shaft causing the case to leak? It shakes pretty damn bad. Maybe he broke something in the t case with his ramp stunt? The. Transmission shop didnt notice any leaks, and id thik theyd have spotted one had it been there. Any ideas???

350Ci
Th350c
Np208.... the owner said he thought it was a 205 but if so its not factory

 

[shady]

stock axles? or 8 lug?

 

[Kaiser85]

Stock 6 lug.

 

[shady]

possible he broke the case or messed up the driveshaft

 

[Kaiser85]

Yeah... im thinking it may have cracked the case or something. It sounds like a janked.up drive shaft though.

 

[rampage]

Is it possible that the PO changed the gears in the rear and not the front? Going in a straight line up a ramp in 4wd shouldn't cause problems unless the gears don't match.

 

[Kaiser85]

I very seriously doubt it.

 

[Kaiser85]

Say something in the transfer case broke, could that cause a bad shake at speed. It sems to leessen during hard aceleration

 

[Kain]

check the u-joints see if you have a bad one

 

[Kaiser85]

They appeared to be okay yesterday.... interestingly enough, theres 2 spares in the glove box

 

[Kaiser85]

Just drove the k5. Noted some things-

Theres absolutely zero vibration or shaking coming thru the transfer case shifter.... that being said. I CANNOT shift the case into N or 4L. Its like the lever wont budge. My old ford had to push down on the stick to get it to 4L, But i dont think thats the case here.

4H is fine.

Truck still shakes like a mofo, but i dont think its coming from the transfer case.... either way, it still leaks

 

[shady]

if the rear shaft has a double cardan joint in it the center ball may be toast that could cause some high vibes. i'd think it would do it before 50 though maybe you have a broken belt in a tire, it woulb probly balance out on a machine but on the truck would make a difference

 

[Kaiser85]

See, that is what im thinking. Or a flat spot or something. Its FEELS like a tire thing, like theyre put of balance, but theyre balanced well. Ill see if i can locate a some wheels to swap and see

 

[shady]

its a PITA but you can take them off and roll them to see if one rolls odd. ive done it before and found a bad one

 

[Kaiser85]

Ill give it a shot. That couldnt have been seen on the balancer. I know my untrained eye was watching for it

Akso, any ideas on why i can oly shift into 4h. When i keep trying to pull back into N and 4l, its like the shifter is STUCK. wont budge

 

[shady]

just a thought but, you are in neutral and pushing twards the passenger side a little before you pull back the rest of the way right?

 

[Kaiser85]

I was in neutral.... didnt know i had to move it.towards the pass side. Lol. Ill try that

 

[Kaiser85]

Uhhh...... this may be it..... lol

The slip yoke has play in it too. Normal?

 

[Kain]

that will do it, the tab that keeps it in place looks to be gone need to check and make sure its there or you will have to replace the yoke.

 

[kyrow]

I know I am a noob, but what is it in the yoke image that you guys see? Is it that the u-joint cap is sliding off? Isn't the strap supposed to keep it on? Thanks guys.