richard howard

O.K. dodge guru's figure this one out. Dodge ram 1500 4x4 quad, 100,500 miles
and new balanced tires, brakes and rotors. When initially taking off from
stop, and without touching gas, truck shutters ever so slightly but enough to
see out rear view mirror. As soon as I touch the gas its gone, or if I reach
3-4 mph. It doesnt do it any other time. If I hold the brake and let it roll
at 1-2 mph it will continue to shutter, almost hop. Is it the Torque
converter going bad, something else? The fluid, and filter where changed
(with proper fluid) but no improvement.

tom lawrence

Driveline shudder, caused by a worn U-joint.

bob snyder

Isn't it common fo the lock-up unit on these to be a failure point?
Wouldn't that shudder at very low speeds as it tries to lock up prematurely?

jon

Richard -- I think I've got your answer. I chased the exact same
symptom for a year in my '97 318 @ 103K because of its variability:
some days it was there, some days it wasn't. Eventually I was led to
discover the fragile nature of the magnum cylinder head -- cracked
valve seats. Not enough to see in a vacuum flutter or compression
test, and not big enough to push coolant out or suck it in, but enough
to get CO in the antifreeze. The ever-so-soft cylinder just fires with
a little less gusto under high vacuum conditions -- your no-throttle
take-off. As soon as you crack the throttle open, the higher load
completely masks the symptom.

Run a test for CO in your antifreeze, and/or a leakdown test if these
conditions make sense to you and your truck, and let us know.

FYI: think about where you put your money....I was in a bind on a
Sunday afternoon, and we magnafluxed a dozen "core" units -- all
cracked on the valve seat. I settled with an awful pair of new Asian
castings for cheap money to get the truck running, but one failed
before I was "ready" to sell it and move on...so personally I rolled
the dice with an ebay reman'd OEM unit. For my money, however, the
bare pair from Hughes plus a local valve refacing would be the way to
go...it's priced right.

Jon

richard howard via carkb.com

Thanks all, I will start with the u-joints since its easiest and cheepest and
work through the other solutions, thanks for the input. Richard

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john

Richard - I'd be interested in hearing what you find out. I have a
2003 I just bought with 33k miles on it - similar situation. I don't
notice it visibly in the mirror buti can feel it - not quite all the
time, but most of the time. My gut feeling was directing me towards
driveline in some fashion.

If you can't post it here, please let me know at

" john.redcord AT gmail.com "

Thanks,

Robert

tom lawrence

If you've had it all the time, and you have a vehicle with a two-piece
driveshaft, sometimes shimming the center carrier bearing mount (adds a bit
of angle on the front U-joint, lessens the angle on the rear) can cure this.
I didn't mention this to the OP, because he said it had only recently
developed.

Also, some have reported (Roy here being one of them, IIRC) that a procedure
to "align the drivetrain" has cured this shudder. This involves loosening
the engine and transmission mounts, driving forward about 100ft., driving
backward the same distance, then re-tighten the mounts WITHOUT moving the
vehicle. It seems some drivetrains were installed in a slight bind, and
this has been shown to cure some shudder-on-takeoff problems.

richard howard via carkb.com

I will, plan to work on it Thursday


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