front end vibration

[v-8power]

My truck is a 84 with 302/aod

It drives good for the most part, when i get up to 60 to 65 it vibrates/shimmy's real bad. If i slow down or speed up it seems to get better.

When i first got the truck the wheel bearings were finger tight.

I torqued those to spec and it seemed to help some. But I'm out of ideas now.

Also i have tried pushing the break pedal to see if it went away. I didn't notice a difference. I really would appreciate any suggestions on things to try. Thanks, Brian

 

[Young_unn]

i am assuming this is a 2wd, if you havent already checked all the front end i would do it. if you feel a wobble at slow speeds check the tires, you can check the balance on the to, try to swap the wheels around.

is it lifted or lowered?

if the whole car shakes check everything that spins, check u joints?

does the pedel shimmy when you press it at that speed?

 

[strvger]

have your tires rebalanced. have them double check the wheel bearings then the brakes after the tires are off. i don't think even the worst misalignment would cause vibrations like what you are describing. if you've checked everything else, the only things left are bent axles or drive shaft. good luck!!

 

[v-8power]

Thanks for the ideas.

A while back i had the front tires balanced. I am thinking i might repack my wheel bearings today. Also i think my drive shaft is about 2" shorter then what it should be. Not a lot of yoke sticking into the tranny. I'll post as I get around to trying things. Thanks again for the replys

 

[matt0528]

ball joints

 

[Duane867]

1st, check tire pressure and the tires themselves for raised surfaces and flat spots and check your front discs out.

Then...
Check your ball joints, tie rod ends, wheel bearings, U-joints etc etc etc.....

If you strike out there.....
I would hazard a guess your trans cross member has been relocated back about 4-5 inches as well as a shortened drive shaft. Check the bolts and bushings on the cross member mounts, and check to see if the weight has fallen off the drive shaft ( will look like a little iron square welded to the shaft).

 

[v-8power]

I took the drive shaft out and measured from the flange to the seal. It measured 55", my drive shaft itself is only 56" long. I'm thinking this is the problem. Taking it today to be lengthened. I should have it back tonight or tomorrow. I'll post the results. Thanks for the suggestions.

 

[Duane867]

So, from the rear end flange to the tail of the transmission is 55" and the shaft from rear flange to the tip of the splined input shaft is 56 " long ?

Yup thats a recipe for disaster in more ways then one. You could flex out over a pot hole and the shaft could fall out. You're probably getting all manner of wobble out of that bugger. You need to measure for a new shaft with the input side of the shaft all the way seated forward in the tail housing then take the distance your lacking or over from a complete jammed in place fit and subtract about 1 1/4" - 1.5" max. That'll give you enough play to flex and enough shank to stay put flexed out.
Good thing you measured that shaft.
How much spline was showing ? bout' 3 inches or so huh ?
Wow.. I would check every swap part on the truck out thoroughly now if it were me.
Trans mount, trans X member, Exhaust, engine cradle and dog house frame for notches that may have been to wide with no reinforcement, trans dip stick, engine mounts.. filter relocation kit and the works.
Sort of sounds like the guys who did the swap half assed it where it counts but ,maybe they didn't

 

[v-8power]

They told me to measure from the flange to the lip of the seal for my new shaft. Unfortunately they didn't get it done today. Yes there was a lot of the yoke showing. lol

I have checked out most of the truck and found a couple things that need redone. Just wanting to do them one at a time to see what helps the most. It's a work in progress. lol

 

[v-8power]

So i got the new shaft put in tonight. Fit nice. Jump in it to take it for a test drive. It cranked over for about a second then nothing. No power at all to anything. So after i figure this out I'll let you know about how the shaft helped. lol Thanks for the ideas guys.

 

[Duane867]

Carb or fuel injection ?
1st thing I would check would be battery ground and positive cables and main fuses.

 

[v-8power]

I just jumped it and it fired right up. I got to take for a drive and it helped ALOT. I still have some vibration witch I think is coming from the tranny. My output shaft had a BUNCH of play in it. I figure that old shaft messed it up. So I'll save up some more pennies and get a rebuild kit for the AOD. Thanks for all the suggestions.

I do plan on doing ball joints and tie-rod ends. I have them just haven't had time to get them on.

 

[Duane867]

Depending on how much you love this truck you will be better off buying a REMANUFACTURED ( NOT REBUILT ) transmission versus rebuilding it your self.
Its incredibly hard to do your self on the garage floor. You need special tools, a parts cleaner, and all manner of crap.

 

[v-8power]

Depending on how much you love this truck you will be better off buying a REMANUFACTURED ( NOT REBUILT ) transmission versus rebuilding it your self.
Its incredibly hard to do your self on the garage floor. You need special tools, a parts cleaner, and all manner of crap.

I had considered this. A friend of mine used to have a tranny shop. He said he would help for a nominal fee. When it actually comes time to do though, i will have to weigh my options and see what is best, at that time.


On a side note, I am swapping out the open 3.08 for a 4.10 posi saturday. that should help performance.

 

[Duane867]

and beat the remaining snot out of your already whimpering transmission LOL !

Be sure you replace the hard parts as well as the soft parts in your transmission when you rebuild it. Hard parts meaning servo pistons and such. You're already there when you tear it down so do it right ;-)