I would really appreciate some input on this not sure if its tranny or done
motor . 2001 15000 4x4 360 a couple weeks ago we were on a road trip
and when i tried to accell a few time hiway speeds i heard a timing knock.I
figured it was crappy gas but havent heard that sound in many years .It
has had a long shift usually from 1st especially if you are on the accell it
would hit 3 grand and still be at 20 mph, you would have to let off the gas
to get it to shift before it sounded like it was at its limit.Then yesterday the
thing wouldnt go over 40 mph you could hear the throaty bog of the engine
but no go ,If you did get it to 50 on a flat long stretch it felt like it was
towing a boing 727 with no wheels and you could also seethe temp gauge
start to raise .Its seems like tranny almost feelslike the convertor is locked
up and have had a feeling the tranny was on its way .Ive seen lot sof
complaints on trannys in this but no real symptoms its does have 150k
miles on it , Thanks

 

You need to do some basic tests to see what condition of motor is. Could be clogged cat, remove front O2 sensor and see if it runs better without it. Did you replace your plenum gasket yet? Do a compression test and leakdown test and check vacuum. No easy answer here without doing some checks.

 

Transmission solenoid? Mine just went bad, and has some of the same symptoms you describe (checked the engine code with the OBD-1 "key dance"). Do a diagnostic and see what codes are being thrown.

 

I spoke to my son inlaws best friends hes a tranny tech and doesnt think its the tranny but says a pressure solenoid for the tranny is on the same circuit as the 02 sensor also think cat plugged but was replace 3 or 4 years ago and not many miles since maybe 5000 ,Spoke to my tech and hes leaning toward cat as well but taking it in tomorrow im hoping they can do a cylinder balance test still with these new diag tools,I did get the code for the 02 cleared and the issue still remains .Fingers crossed for tomorrow thanks for the input even if its the cat im gonna take it to the tranny guy after , got a long tow coming up I hope!!

 

check exhaust system pressure before the cat first. That sounds a LOT like your problem.

has the plenum ever been fixed? Burning oil will smoke a cat in pretty short order.

 

plenum was checked out a few years ago and the exhaust does leak i spoke the husband of my deceased best friend and was under the influence it was a oem replaced cat but find out its a aftermarket weld in so that could be.The fuel pump was replaced once but 5 years or more It does smoke but very little and thinking back most of teh ping and accell started after filling up here one day at Canadian Tire but since then filled again else where ,Why would Dodge not put an inline filter like most normal people.What was the plenum issues vac leaks im assuming

 

The filter is part of the fuel pump module, and isn't precisely easy to change.

If the gas at Canadian tire hangs out in the tanks for any appreciable length of time, it absorbs water right out of the air...... water doesn't burn good, so, the engine runs like... well. You know. Not to mention the alcohol separating out..... (alcohol in gas to reduce our dependence on foreign oil was just plain idiotic.)

The intake manifold is two pieces, the big aluminum 'kegger', with a steel pan that bolts on to the bottom, to seal it all up. That gasket there likes to blow out, and then you get a major vacuum leak, and give the engine the ability to suck oil right out of the valley there...... burning oil really does a number on cats. May not hurt to have that checked again. (just pull the throttle body, and have a look.) Doesn't do wonders for O2 sensors either.......

 

How the trans fluid level? I had those same symptoms when my grand prix was low many years ago. Lack of power with higher than normal revs.

 

First off thank you all for your input its very much appreciated Turns out the previous owner had replaced the cat but not with the one I had suggested and it turns out this one was undersized as well as cracked and plugged up from falling apart inside .Had i new larger magnum installed and the extension pipe ( stainless) and a new 02 fitting for under 400 now i find that the shop i paid to put ball joints in the RF not only screwed up the top ball joint where i had to have it welded in last year they didnt seat the lower ball joint so its worn the knuckle oval at least it isnt falling out now to find a knuckle not much close to me at the wreckers

 

Replacing just the axle side knuckle is a major pain, and folks doing it in a shop rarely get it right. If there isn't anything else you can do with it, replace the entire axle.