I have a 1999 Dodge Ram 1500 van, 3.9l, three spd auto. When I hit the gas lightly she accelerates nice and smooth, if I hit the gas normal it shutters and vibrates the whole van pretty badly, if I floor it she accelerates nice and smooth as well.
So my thoughts are that it is either the torque converter, or the bushing in the rear part of the transmission where the drive shaft enters. Also really need to change the fluid as it is really more of a brown color rather than red.
Anybody have any ideas? It's not motor mounts or tranny mount they are all new and I've checked them for cracks. I'm stumped....

 

Mainly your problem sounds more like the ignition wire routing TSB than the tranny.

Try this first ...
http://dodgeram.info/tsb/1998/18-48-98/18-48-98-v8.htm

If the tranny fluid is dark brown, get a typical flushing with new filter and screen. ONLY use ATF+4 and no substitutes. Anything else will ruin the tranny.

 

I will check my wire routing but it doesn't exhibit any of the symptoms described. It really feels like to me that the torque converter is shuttering. But never had one fail like that before. I wonder if it could just be dirty oil.

 

get the fluid changed or tranny flushed if less than 100K miles

I had a slight shudder at freeway speeds that went away after changing fluid in my old '94 B250

 

If the fluid is brown, it is worn out, and continued operation with brown fluid will accelerate any issues.

Will new ATF+4 cure the issue?
One can hope.

However most places which do such services will not use ATF+4. they will have some such universal fluid to which they will add a "magical" friction modifier which they claim will take subpar tranny fluid with the wrong friction modifiers and magically turn it into ATF+4.

ATF+4 is synthetic. It resists shearing and thermal breakdown better than 95% of all other transmission fluids out there, and is the only correct fluid for our transmissions. Putting a 'magical' additive in Dexron2 is not going to come close to atf+4, but nearly every mechanic out there, who makes money on "flushes" will tell you so.

A problem with "flushes" is they are usually done on a neglected transmission that is already on its last legs, and the "Flush" pushes it over that edge.

Perhaps "Fluid exchange" would be a more desirable process, as long as the pan is dropped and the filter is changed.

"Flushing" does not require the pan to be dropped and the filter changed. "flushing" with fresh fluid might clog the filter and cause failure.

Just dropping the transmission pan and changing the filter will only get about half, or slightly less of the old fluid out and renewed/Diluted when refilled.

Ideally you want the fluid exchanged, then the pan dropped, the filter changed, and 4.xx more quarts of fresh ATF+4 to replace.

This does not guarantee transmission issues will be averted, but anything other than this with a dodge van transmission is likely to cause failure and rebuild or just another van in the boneyard for others to salvage parts from.

I recommend dropping the pan, installing a drain plug, changing the filter, adjusting the bands, refilling with atf+4, then a week later, dropping 4 more quarts via the new drain plug, and replacing with fresh fluid, and again perhaps a month later, If and only IF it responded favorably to such treatment.

If it did not "like" the initial 4 quarts of new fluid, start saving for a rebuild.

But do make sure the engine is not just misfiring at a certain speed and load because your 6 month old spark plug wires could not possible be bad, cause they are only six months old.

Those days are long gone. The parts we have access to today are built to the lowest 'acceptable' standard, because the brand names we used to co-relate with quality , have sold out, and their Asian managers quickly cut all quality control once the first shipped batch "passes"

Baby needs a new diamond.

 

Thanks for the tip on the change or flush. I will exchange it little by little. I assume there is a thread on adjusting the bands on the tranny? I can't seem to find anything on the three speed.

 

The Hayes manual is slightly better than the chiltons' to change and adjust the bands for the RH and RE trannies. That is one good reason I bought the Hayes over the Chilton.

I would concur 100% with LY about the ATF+4 and the process mentioned above.

And another piece of warning ... DO NOT EVER take your van to service the tranny at AAMCO period.

 

 

I am going to change the oil and adjust bands tomorrow. Ill see if they have a manual in stock and pick one up for the band adjustment.
Anyone know what my tranny model is called? 6-239 is the only number I can find but when I look for parts under that they are early 90's models. Mine is a 1999 3.9L 3 spd, with a 32 gallon tank and shorter wheel base.

 

Do you have an accurate inch pound torque wrench?

Kind of hard to get an accurate reading unless the van is well off the ground.


I believe you have a 32rh or 32re transmission.