Update on KJ's truck/vibration problem

Thanks group. My truck is running, insured, and inspected. I however do have a vague problem, so I will detail all that I know about it.

1985' Chevrolet K5 305CUI SB bowtie power plant TH700R4 transmission - used from a 1983 GMC Jimmy NP203 transfer case - original

Recent Repairs: New front brake line, from proportioning valve to flexible brake line. New transmission cooler lines (too and from) Three new U-joints (both on rear axle, front on front axle) New: oil, tranny fluid (transmission and t-case), new oil filter, air filter, wipers

History of transmission repair: Last transmission wouldn't shift out of first, and was low on fluid when I dropped it. The pan was FULL of metal shavings. My guess is I found the reason why the first tranny failed when I finally found the source of the leak. It was an "obvious" leak and also well hidden in a pipe bend out-of-sight. I actually thought the cooler was plugged, and every once in a while fluid was coming up the fill tube and coating the passenger side engine compartment. Gary had described this, so I thought maybe I had a partially clogged cooler.

U-Joint repair: They weren't bad. I lost some needle bearings in the dirt from the rear drive shaft, so I just decided to get a new joint, then decided to change them all so I knew they were all good. They seated right, have all their bearings, and are full of grease. I haven't gotten the cardian joint apart, nor have I tried. The truck is currently a 2x4 only - no front drive shaft.

Carburetor repair: The carb is somewhat sorted out, it still starts hard (like the choke is pulled open too early) but it opens fully when running, so I don't get horrible gas mileage. Plug wires look good, haven't pulled the plugs yet though.

Wheels/Tires: The truck was supposed to have had new tires, rotation, alignment, and balancing all done by NTP (NPT?) recently before I bought it. There were a bunch of slips detailing all the work, and some receipts for things he had done (new fuel pump, the one on the engine). I didn't look too closely, so I don't know how long ago this was. I also can't vouch for his mechanical aptitude. I can always tell where he did some work?missing screws, different screws. When you have 3 bolts on a torque converter, and 2 different sizes???. That kind of thing.

However the wheels are a deep-dish mag design. The previous owner put acorn lug nuts on, (or just reused when he got the new rims) and just tightened them balls tight. Annoyingly, the lug nuts are not even all the same size. When doing a self-inspection of the brakes, I was able to get ONE wheel off- that's it. I tightened it back down, and later on that day I lost all my lugs and luckily not the wheel! Then it was explained to me why this had happened, so I didn't feel like ?as much' of a retard. I've now seen the mag lugs with the shaft that's meant to go into the rim?. so now I know what I need to stop that from ever happening again. Right now, there just tightened balls to the walls?..However I suspect that the damaged rim might not be "self centering" the way it's supposed to. And here follows the problem.

PROBLEM: Vibration. I have a vibration from around 35MPH to 40MPH and from

63MPH(ish) to about 73MPH(ish). It doesn't seem to be coming from any one area, (front/back, left/right) but just EVERYWHERE?. The driver's side rear view even rattles?

My guess is a balance problem, since the problem reiterates at multiples of 2 (with a stronger intensity, and wider speed range). At any other speed, the truck doesn't shake at all. It doesn't pull off to any one side, stays relatively straight. It doesn't seem to effect "drivability" at all. I personally haven't put many miles on my tires, but I don't see any abnormal wear signs (yet).

BIGGER PROBLEM: I haven't done any driveline work of this kind, and only vaguely know how things work. And since I want to be the only one to twist wrench on my K5, I'll have to learn. Looking underneath the truck, I don't see any blatant problems, and one side generally looks like the other. I know there is A LOT more to alignment then "looks" though. So my question is: where should I start looking for the source of this problem? Does it seem like a balancing problem, and drive line problem, etc?

-The Lonely Grease Monkey

1985' K5 305CUI TH700R4 NP203 KJ's successor

"Ignorance is preferable to error; and he is less remote from the truth who believes nothing, then he who believes what is a wrong." - Thomas Jefferson

Reply to
Lonely G-Monkey
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Step one when chasing down a problem like this is to fix what you know is broke. Namely the lug nuts. If it's damaged the rims, replace as necessary.

If that doesn't fix it, have someone follow you down the highway, looking for a bent rim or a tire out of round/blistered. If you have a vibration as low as 35, it's probably not balance. You could also put the car up on jackstands and run it to look for this. Be safe, make sure someone stays in it while running. Put it in 4 wheel, and just let off the brake. No need for any speed.

Reply to
John Alt

As another poster pointed out, check your drive line. If you have a 'short' shaft, inspect the u-joints. Short shafts are prone to vibration. Look for 'Any' play in the u-joints. replace and balance, in that order.

Cheers

Reply to
Martin Riddle

. . . KJ, Did you have "ANY" trouble bolting the tranny and the t-case up???

ANY???....and think real hard, anything that took a little extry oomph to persuade to pull up tight??

Hear "ANYTHING"...go "pop"?

jack up the rear and idle it in 1st and take a look at the drive shaft and rear wheels while they're turning. It's definately not in the front, make sure those two are not bouncing around. Make sure the motor mounts and the tranny mount are in good shape.

then......lodge you a stick in there on the gas pedal and get it running at around 40mph and take a look under it............see if the tranny is vibrating it's arse off.

sounds like it might be consistent with 2nd and

4th gear apply......or lockup. Let's hope not.

ps....good pics on the other post.....truck wasn't as ugly as I imagined.

marsh ~:~

Update on KJ's truck/vibration problem Group: alt.trucks.chevy Date: Tue, Nov 4, 2003, 11:32am (CST-2) From: pde_on snipped-for-privacy@hotmail.com (Lonely=A0G-Monkey) Thanks group. My truck is running, insured, and inspected. I however do have a vague problem, so I will detail all that I know about it.

1985' Chevrolet K5 305CUI SB bowtie power plant TH700R4 transmission - used from a 1983 GMC Jimmy NP203 transfer case - original Recent Repairs: New front brake line, from proportioning valve to flexible brake line. New transmission cooler lines (too and from) Three new U-joints (both on rear axle, front on front axle) New: oil, tranny fluid (transmission and t-case), new oil filter, air filter, wipers History of transmission repair: Last transmission wouldn't shift out of first, and was low on fluid when I dropped it. The pan was FULL of metal shavings. My guess is I found the reason why the first tranny failed when I finally found the source of the leak. It was an "obvious" leak and also well hidden in a pipe bend out-of-sight. I actually thought the cooler was plugged, and every once in a while fluid was coming up the fill tube and coating the passenger side engine compartment. Gary had described this, so I thought maybe I had a partially clogged cooler. U-Joint repair: They weren't bad. I lost some needle bearings in the dirt from the rear drive shaft, so I just decided to get a new joint, then decided to change them all so I knew they were all good. They seated right, have all their bearings, and are full of grease. I haven't gotten the cardian joint apart, nor have I tried. The truck is currently a 2x4 only - no front drive shaft. Carburetor repair: The carb is somewhat sorted out, it still starts hard (like the choke is pulled open too early) but it opens fully when running, so I don't get horrible gas mileage. Plug wires look good, haven't pulled the plugs yet though. Wheels/Tires: The truck was supposed to have had new tires, rotation, alignment, and balancing all done by NTP (NPT?) recently before I bought it. There were a bunch of slips detailing all the work, and some receipts for things he had done (new fuel pump, the one on the engine). I didn't look too closely, so I don't know how long ago this was. I also can't vouch for his mechanical aptitude. I can always tell where he did some work=85missing screws, different screws. When you have 3 bolts on a torque converter, and 2 different sizes=85=85=85. That kind of thing. However the wheels are a deep-dish mag design. The previous owner put acorn lug nuts on, (or just reused when he got the new rims) and just tightened them balls tight. Annoyingly, the lug nuts are not even all the same size. When doing a self-inspection of the brakes, I was able to get ONE wheel off- that's it. I tightened it back down, and later on that day I lost all my lugs and luckily not the wheel! Then it was explained to me why this had happened, so I didn't feel like 'as much' of a retard. I've now seen the mag lugs with the shaft that's meant to go into the rim=85. so now I know what I need to stop that from ever happening again. Right now, there just tightened balls to the walls=85..However I suspect that the damaged rim might not be "self centering" the way it's supposed to. And here follows the problem. PROBLEM: Vibration. I have a vibration from around 35MPH to 40MPH and from 63MPH(ish) to about 73MPH(ish). It doesn't seem to be coming from any one area, (front/back, left/right) but just EVERYWHERE=85. The driver's side rear view even rattles=85 My guess is a balance problem, since the problem reiterates at multiples of 2 (with a stronger intensity, and wider speed range). At any other speed, the truck doesn't shake at all. It doesn't pull off to any one side, stays relatively straight. It doesn't seem to effect "drivability" at all. I personally haven't put many miles on my tires, but I don't see any abnormal wear signs (yet). BIGGER PROBLEM: I haven't done any driveline work of this kind, and only vaguely know how things work. And since I want to be the only one to twist wrench on my K5, I'll have to learn. Looking underneath the truck, I don't see any blatant problems, and one side generally looks like the other. I know there is A LOT more to alignment then "looks" though. So my question is: where should I start looking for the source of this problem? Does it seem like a balancing problem, and drive line problem, etc?

-The Lonely Grease Monkey

1985' K5 305CUI TH700R4 NP203 KJ's successor "Ignorance is preferable to error; and he is less remote from the truth who believes nothing, then he who believes what is a wrong." =A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0= =A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0= =A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0= =A0=A0=A0=A0=A0- Thomas Jefferson
Reply to
Marsh Monster

Sorry, that is what I gathered from the NG's guesses. It may be totally wrong. It is not an all-time 4wd gear box, and it takes Dextron fluid. I think someone said it should be an NP208 in my truck? I am almost 100% sure it's stock, only because it isn't reman... the TH700R4 that came out was reman....

-The Lonely Grease Monkey

1985' K5 305CUI TH700R4 NP203 KJ's successor

"Ignorance is preferable to error; and he is less remote from the truth who believes nothing, then he who believes what is a wrong." - Thomas Jefferson

Reply to
Lonely G-Monkey

shaft, inspect the

replace and balance, in

Guess I wasn't clear enough. All the U-Joints running in this truck right now are brand new. I haven't had the shaft ballanced yet though.

-The Lonely Grease Monkey

1985' K5 305CUI TH700R4 NP208 KJ's successor

"Ignorance is preferable to error; and he is less remote from the truth who believes nothing, then he who believes what is a wrong." - Thomas Jefferson

Reply to
Lonely G-Monkey

Of course I had trouble. I was on my back, in a dirt drive way, with 1 short floor jack and no help. I suppose "any" is relative though. One thing I had troube with is the TC and flex plate. I had 0 problems attaching the tranny, and then I attached the T-case, and then the rear drive shaft. Last I went to attach the TC. In fighting up the tranny it had come off the tranny shaft, and was now un-movable and bending the flex plate. I used a cold chistle and slowly (1 tooth at a time) moved the flex plate around, until it seated... with quite a loud pop..... It did look like all the flex was in the flex plate (no pun intended) but that clunk couldn't have been good for any seals in the way (would not have liked to have had my hand inbetween the tc and the tranny!!!)

I know you've read it, but I didn't apply (what I thought) was any extra force to anything....

Haven't closely inspected the motor mounts, but the tranny mount is somewhat sad... I'll try to get a picture up. The best I can describe it is "rust covered rubber". I couldn't actually describe the way it came, OEM.

Remember what I said about you sounding like a neaderthal.... I think it's time to call on my friends with the lift.... :-) Or at least bother my girl friend to run it at 35 (Thats what my S10's manual says you can slip the wheels up to on snow).

I'm hoping not as well, but now that you bring it up... haven't been too happy with the shifts. If this tranny is crap, I'm just gunna get a manual, 4 on the floor.... eff this stupid auto shit.

Anyone got someone who might have a good 4speed bolt-on for my aplication? With all needed linkage/pedals/etc?

You should see it now though! 1/2 gallon of bondo makes a big difference, and I still need to put more on. Even then, it might be all nice and smooth but in 6 months the cancer will have spread more... sigh.... It's a great truck and all but it wont be a "forever" truck, and I'm not going to put money into 'saving' it per say. I'd rather have a 72-73 (to match my fav vintage of vehicles/bikes) so it's full convertable... :-)

-The Lonely Grease Monkey

1985' K5 305CUI TH700R4 NP208 KJ's successor

"Ignorance is preferable to error; and he is less remote from the truth who believes nothing, then he who believes what is a wrong." - Thomas Jefferson

Reply to
Lonely G-Monkey

. . =3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D KJ, =A0=A0=A0Did you have "ANY" trouble bolting the tranny and the t-case up??? ANY???....and think real hard, anything that took a little extry oomph to persuade to pull up tight?? =3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D

2003, 11:39am (CST-2) From: pde_on snipped-for-privacy@hotmail.com (Lonely=A0G-Monkey)

Of course I had trouble. I was on my back, in a dirt drive way, with 1 short floor jack and no help. I suppose "any" is relative though. One thing I had troube with is the TC and flex plate. I had 0 problems attaching the tranny, and then I attached the T-case, and then the rear drive shaft.

Last I went to attach the TC. In fighting up the tranny it had come off the tranny shaft, and was now un-movable and bending the flex plate.

I used a cold chistle and slowly (1 tooth at a time) moved the flex plate around, until it seated... with quite a loud pop..... It did look like all the flex was in the flex plate (no pun intended) but that clunk couldn't have been good for any seals in the way (would not have liked to have had my hand inbetween the tc and the tranny!!!) =3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D "greasy monkey man".... you know......when I read the post the first time, first thing I started to ask was if you heard a pop when you tightened up the convertor.... then I thunks fer a second.....and i tell muhself... "the monkey will lie and say no"... so's i went ahead and reworded the question.

:)

me thinks you may have warped the flywheel....

let's hope not,

scrib ~:~ =3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D

Reply to
Scrib Abell

"greasy monkey man".... you know......when I read the post the first time, first thing I started to ask was if you heard a pop when you tightened up the convertor.... then I thunks fer a second.....and i tell muhself... "the monkey will lie and say no"... so's i went ahead and reworded the question. :) me thinks you may have warped the flywheel.... let's hope not, scrib ~:~

You've never steered me wrong, but this does seam weird. Looking at the consol, it seams very much like it's a side-side vibration. Sometimes it can be very pronounced, side-side.... It seams to me like this could only be an out of balance flex-plate (not manual not flywheel). Not a warped one - which I would think would be a wobble problem and cause an all-around vibration.

Still haven't checked the wheels like you told me too - just been too darn cold.

I've noticed that the front wheels have some weird tread wear. The outside have scruff marks, like normal. The inside is kinda chunked, like the edges are ripped off it.

Trailing edges of the tread are lower then the front (front meaning towards front of the truck). This is looking on the top of the tire, so it would be low edges up front on the road. Dramatic dramatization: /|/|/|/|/|

I've noticed that steering is somewhat vague, IE if I don't constantly watch the road (look at my mirrors for an extended period of time, kick the radio, etc) it will wander - my S10 did not. I could feel the road just slightly, if you know what I mean.

Travels relatively straight otherwise.

Thanks scribbs, got any input on my novice 4x4 questions?

~KJ~

Reply to
KJ

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