So, in a previous thread I had a snapped distributor shaft and after replacing the dizzy I got back out on the road. While driving I noticed that if I maintained a speed between 35-55 that the truck would shudder, shake, or kinda shimmy. This shake would go away as soon as I accelerated or completely let off the gas but if I held the pedal in the "sweet spot," to maintain a speed it'd come back and then occasionally disappear and reappear intermittently. Not particularly violently but enough to cause some concern, so I took it to a tire shop and had them look at the rear tires because it was something I felt in the seat, not the steering. I had one of my rear tires replaced but the issue remains. I'm sort of unsure of what it could be, and suspecting something like U-joints I crawled under the truck and grabbed the drive-shaft and gave it a good yank and pull and there's almost no slack at all aside from a little backlash lee-way. My concern is that it's the torque converter, but I've never had problems with the transmission, it shifts so smooth it's almost not noticeable and there aren't any grinding or particularly nasty noises. Any thoughts?

 

the 35 MPH shudder mostly on deceleration i have seen on 70% of the chrysler cars / trucks i have owned. iam not sure it is serious trouble. but dont be afraid to check things out, just to be sure.

 

my 2009 nitro did that @ 70km/h from new till day I forced Chrysler to arbitration and take it back cause it was unacceptable :O it was issue with transmission going into overdrive to soon and rpm's would drop to low.. kinda like a standard in 5th gear @ 30km/h (sorry im cnd. I use less superior km's)

my buddies ranger did that and ended up needed front shocks, balljoints and a wheel bearing..

 

overdrive to soon? my 01 dak V6 42 trans after i had a 4.1 gear., put in. my MPG went from 8-9 to 11-12. and goes into O.D. at 30 MPH AND the V6 pulls it. at 40 MPH the tach is at 1400 RPM. course i drive ONLY in town.

 

I said its a possibility.... my nitro was dropping below 1k rpms.... ever shift from 1st gear to 5th in a standard..... man if my neon shook like that it would fall apart... and it went away if I shut off overdrive or drop over 80km's (1200 rpm's) doing 65mph this thing was 1400-1500 rpms in OD 3.9 and was insanely good on highway for fuel .. averaging 34mpg anyway


back to OP....

my G6 would have random shaking and it was caused by 2 things... yes aftermarket rims, on one side threw a stickem weight but also one strut mount(same one tire was one) was worn and allowing tire to vibratye entire vehicle , I know u don't got struts but maybe something up front worn out ..

 

I had that problem with my Lumina a few years ago. Turned out that it was a bad spark plug wire--it caused a speed/rpm specific vibration.

 

Well, I have new 7.5 spark plug wires and a new distributor body, new rotor, and new plugs, so I doubt any of those are the cause. Like I said it only shows up when maintaining to aforementioned speeds. I'm beginning to wonder if it might be a dirty injector from backfiring through the throttle body the few times I tried to start it with the snapped dizzy shaft. It wasn't a problem before a snapped the dizzy and wasn't present at all, and then as soon as I got it started after replacing the distributor it showed up. It goes away if I press the gas in and accelerate or let of the gas and decelerate. It's kind of aggravating. After the holidays I'll tinker with it and pull and inspect the plugs and clean the throttle body and unplug the egr and check for vacuum leaks among other things. If nothing else I'll replace the other rear tire and see if that fixes it and if not I'll replace the universal joints.

 

TO: 92DakotaClub i apologize i was not trying to say yours didnt do that or couldn't do that. and i wasnt saying you were telling a fib. i was just trying to say how one could act. as you know cars/ trucks can through you a loop over and over. hope you work it out.

 

It is possible that you got a faulty spark plug wire. Even brand new, out of the box. My Lumina had one with less than 5k miles since replacement. Sneaky little baxtard, too, it idled just fine, even ran fine in city driving. But out on the highway it vibrated like h e double hockey sticks! Check them with a multimeter--ohm reading. Look for one that's different from the rest.

Since the problem didn't show up 'til you replaced the distributor, I would vote that your problem is ignition related. Are you 100% sure that the new distributor isn't defective and that you got it in correctly? Check it for wobble, and see that the advancing weights both move freely. Are you sure that you didn't damage the dist. cap installing it? Look close, under bright lights.

Time to stop throwing money at the problem. Don't replace a tire or start doing universal joints. Vibrations in those areas don't suddenly appear. Worn U joints don't generally cause vibration anyhow, but instead a clanking noise when you put the truck in gear or start out from a standing start. Tires that are vibrating can give you visual clues.

 

Well, my truck does idle fine and does fine under thirty five, so I'll test the wires today while the sun's out. I actually had to order two dizzy's because they aren't manufactured and the first reman I got was rusty and I refused to accept it, this one looks new, even down to the contacts on the electrical connector for the advance and retard. I did install it correctly, as far as I know. I installed it 180 degrees out first time and swapped it around and it fired up just fine. How would I check the advancing weights? I'll look at the cap, but I'm doubtful I damaged it. I try to be gentle with everything that I'd rather not have to replace. Thanks.