shudder like problem
 

good morning or afternoon gentlemen and ladies or whom ever reads this.I been silent for a while giving everyone a break from me but it ends today:giggle:. I have not been driving my truck my wife has for sometime now and i was with her yesterday and we where driving with noac at 2000rpm around 70mph and the truck started to shudder . I read some forums in here and some have described it as running over a wash board . My wife said the samething awhile ago butt when it comes to her she is very hard on vehicles and thats saying it nicely .some peopleon here stated it could be a torch converter locking and unlocking someone also said it could be a fluid issue (trans fluid) and to change the filter and such . it doesnt do all the time but she has stated it happen 2twice with her and i felt it yesterday . well thats a start what should i do thanks Shawn

Well one way to tell if its the torque converter locking/unlocking is to monitor the comm gear display on the gryphon. This will tell you what gear your in and you should she a lock when the torque converter locks up...then when the problem occurs, you can look at the display and see if it keeps locking/unlocking. Also if thats the problem you should be seeing a jump in the rpms...probably around 400-500 difference.

I had this same problem last month. Bill said it was a software problem and had me update the Gryphon via Pegasus.

I like this answer, but am bothered by the "shudder" description. Are you sure you're not feeling tire imbalance problems? I had to have my tires rebalanced about three times to get rid of the "shudder" they caused. In other forums, this seemed to be a problem in my model year truck. The vibration in mine was VERY strong in the 65- 70 mph region.

- Jack

Sounds like something mine has been doing for a while. Sometimes I think its the road but then it keeps going when I get to a smooth section. It might just be alignment or tire balance because I dont remember if it was happening before I got new rims. I dont think I threw a weight because the weights are stuck to the inside firmly. :shrug:

Please fill out missing info in your user cp. Like hex and serial number. It will help diagnose problem.
Also what was the terrain like? Hills? Cruise control being used?

Lars

How do i do this, hex code and serial number . The cruise was not on and it was a flat road it doesnt do it all the time once with me with the wife driving and a few times with just the wife. Its not a tire issue because it would do it all the time correct?

Ok never mind i found how to do the hex and serial number sorry a little slow with computer

Generally, that is correct - a suspension/tire problem should show up at all times at a certain speed. But, I found in my truck there were times when it was far more noticeable than at other times. I feel it was a property of the road I was driving on.

The "shudder" description is still bothering me. I interpret that word as describing a very rapid vibration - kind of like a "shiver" when you are very cold. Somehow, I can't visualize how anything in the transmission could cause this kind of rapid oscillation - but an unbalanced tire sure could. It would be a kind of "shaking" sensation that you'd feel in your seat, and if it were from the front end, you'd probably feel it in the steering wheel. As I said, it took about three tries to get my wheels balanced, and I had not thrown any weights - things just seemed to "change" as the new tires "broke in".

I'd expect something funny in the transmission to be a slower effect, and it would have kind of a forward/backward motion. I'd also be surprised to see it happening at 70 mph, unless the truck is under a slight load, perhaps climbing a hill.

I wonder if this could be a somewhat aggressive closed-loop fueling problem? The system there is constantly alternating between too rich and too lean to average things out at the proper stoich, and maybe it's "overshooting"? Just a thought, any experts want to give an opinion on this?

- Jack

After looking at the hex code. The problem "might" require an update. But only Bill would know if this would be the solution. I put a note on the moderator's help board so that Bill will know about it.

That's all I can say or do.

Lars

BTW thanx for entering your info.