bubba211

My friend was driven my car (i was riddin wit hime, of course) and we hit like 95mph on the interstate, and the car started to shake VIOLENTLY, like the front dash and windows going crazy. The ONLY thing i can think of is i need a front wheel alignment bad. could this cause this? or do most rexs do this aroun 90-100mph

peejay

Alignment has nothing to do with it. Alignment will never cause a shake or a vibration.

One or more of your tires is probably out of balance if not out of round. Due to the low-friction steering compnents, and the fact that it's a light car with small tiameter tires, 1st-gens are *very* sensitive to imbalance or out-of-round. I could feel the difference 1/4oz makes at 65mph. I could also feel out-of-round of less than 1/32". My shop manager thought I was nuts when I showed him the "defective" tire ("That's fine, you're just crazy...") but then I took him for a road test and he agreed, you could feel it!

But when everythings round and balanced, you should have no shakes at all. 124mph = smooth as glass.

Since it's that bad, you might also want to check for loose U-joints.

clean85owner

Parts of my car start to fly off at that speed (seriously). The doors and windows shake horribly. I don't think it's tire pressure because my dad makes whoever is driving the car at the time to check the tire pressure once a week.

peejay

Tire pressure won't cause a shake or vibration either.

Shakes and vibrations come from two causes... something rotating is out of balance, or the tread surface of the tire is not round. That's it.

82transam

iTrader: (18)

yep, balance those suckers and you should be fine.

i_piss_on_hondas

yeah if you have a 1st gen check the u joints of your driveline... the like to go out... cant be replaced either... have to replace the whole driveline...

hornbm

if you have to replace the driveline, mazdatrix sells a replacement driveline with changable u-joints for about 100 bux less than the OEM unit.

White84SE

If you have an '81-'83, yes, you CAN replace the u-joints in the driveshaft. It's only the '84 and '85 that have a nonserviceable driveshaft...

--Danny

Amagi82

My last set of tires were balanced so bad that at 100mph you could see the top of the door window moving back and forth about 3 inches. It was downright frightening

V8kilr

dont forget bad u-joints and fix-a-flat in a tire

V8kilr

dont give anyone the wrong idea they are changable, we had this discussion.

you have to remove the old ones and get the new greasable style that the snap rings mount on the inside instead of the outside, I have a shop that has them if anyone needs them.

sorry didnt mean to single you out, this also goes to I **** on hondas and hornbm

RotorMotorDriver

iTrader: (1)

Hmm...Anyone know the visual differences between the drivelines? Anyone have some pictures? When I built my car, I used one of two drivelines I had laying around. I dont know if it was an 83 or 84. If I can change the ones on my 83 driveline, Ill buy new U joints and use that one instead .

~T.J.

rx7gslse

ok, how many times have you driven this "VIOLENTLY" shaking car at ludicrious speed? I suggest you stop until you get it fixed 1st off



2nd, I agree with these guys.. get your wheels balanced.

pillage6

Could be bent rim, that is my problem.

Starts wobbling at about 60mph and the wheels are perfectly balanced, but they said my wheel is bent.

I was curious how a wheel can be balanced and bent at the same time.

mar3

iTrader: (8)

I'm with peejay on this one....if the vibration and shaking is appearing at a certain speed, then it's almost certainly bad U-joints...

lotsacars

Could also be a shifted or broken cord in one of your tires (sounds like a front). I just replaced a set on my daily driver that had a broken cord in one of them. It kinda deforms the tire and wears it funny. It also only vibrated at certain speeds.

ve2cvx

HI,

IS there a way to put a 1981 driveshaft in a 1985. I got one 1981 in good shape and my 1985 is shaking a little bit.

thanks
ve2cvx

bubba211

this is the FIRST time i've ever gone this fast, so its not a habit, ALSO, it only shakes in the front, not the back of the car, so if the u-joints where bad, wouldn't the whole car shake?

RH-7

I'm pretty sure that if I drove my 82 that fast it would blow up.

brownmound

My SE used to shake a bit ~80 mph. Four new tires solved the problem. The previous tires were old, very worn and surely out of balance.

Right on.

OoMazdaSpeedoO

Dang everyones having probs with their cars but yet mine stay smooth all the way to 140mph, one time it started shaking some at 90 so I got the wheels balanced and from then on its been fine

faye x7

I've had my 82 only just above 100mph and my car was smooth as silk.

But anyway..yeah...everybody else has pretty much given you the choices as to what the problem is, no sense in repeating it myself. heh

DBOGGSRX7

I have read here more than once that you cannot replace the u-joints on the earlier (I have an 81) first gens. Last year I had a viberation that seemed to be coming from the transmission / rear of the car. It turned out to be the u-joints on the drive shaft (try shaking it up and down, if it moves, they're shot). Replaceing the u-joints cost $15.00 per u-joint and took about an hour.
Dennis

DBOGGSRX7

Oh yeah, before "spirited" driving of that sort, there are alot of things that need to be checked on your car. Tire unbalance can cause ver ugly problems, all of which will cause you to loose control of the car. others you may want to look into...
Ball joints, tie rod ends (or any other play in the steering), drive belt conditions, Brakes!!!!, Alignment is kind-of-important due to tire temperature at high speeds.. I am sure there are others. I spent a month looking over my car and fixing **** before I drove at "those" sort of speeds.

my 2 ¢

Dennis

1st7heaven

Back in the day when my car was on the street, I had bad window and door seals. The air preasures(inside the car) at those speeds caused the car to vibrate inside......like you said, the whole car would shake!!!