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Possibl transmission issue????

2K views 10 replies 4 participants last post by  HemiFun05 
#1 ·
I dont think I am mechnically savy enough to properly diagnose the issue but my truck does not shift properly during two different scenarios.

1) If I am driving at really any speed (typical street speeds or highway) and accelerate quickly more or less get on it the truck does not shift and just revs up and back fires until I get off of it.

2) At highway speeds trying to accelerate excessively (not getting on it though) the truck does not shift smoothly.

Daily driving just putting around town the truck shifts fine. My problems occur when im trying to accelerate excessivly the truck will not shift smoothly or at all. What do yall think? Definite trans issue?

I have had the fluid and filter changed twice since I have had the truck the most recent by a dealership and that was probably 2 yrs ago and about 30,000 miles. I dont know if that could be it but before I drop alot of cash Id like to know my options. Thanks.
 
#2 ·
I dont think I am mechnically savy enough to properly diagnose the issue but my truck does not shift properly during two different scenarios.

1) If I am driving at really any speed (typical street speeds or highway) and accelerate quickly more or less get on it the truck does not shift and just revs up and back fires until I get off of it.

2) At highway speeds trying to accelerate excessively (not getting on it though) the truck does not shift smoothly.

Daily driving just putting around town the truck shifts fine. My problems occur when im trying to accelerate excessivly the truck will not shift smoothly or at all. What do yall think? Definite trans issue?

I have had the fluid and filter changed twice since I have had the truck the most recent by a dealership and that was probably 2 yrs ago and about 30,000 miles. I dont know if that could be it but before I drop alot of cash Id like to know my options. Thanks.
 
#4 ·
Do you have any gauges to help with the diagnosis? When you say rev"s up and back fires, what rpm are you talking about. Is it banging off the rev limiter?
 
#5 ·
Here's something else you 'might' want to consider - last month my old '99 5.9 Ram daily driver began showing all of the same symptoms you've just mentioned. This occurred AFTER I had added a Seafoam treatment through the intake and the gas tank. I still like Seafoam very much however so much crap was loosened from the intake flush that the converter became almost completely clogged and resulted in the same symptoms you've described. A tune up and new converter solved the problem. I did not get a CEL with the problem so I also thought it was a tranny problem but not so.
Good Luck,

"Doc"
HemiFun05
 
#6 ·
Originally posted by HemiFun05:
Here's something else you 'might' want to consider - last month my old '99 5.9 Ram daily driver began showing all of the same symptoms you've just mentioned. This occurred AFTER I had added a Seafoam treatment through the intake and the gas tank. I still like Seafoam very much however so much crap was loosened from the intake flush that the converter became almost completely clogged and resulted in the same symptoms you've described. A tune up and new converter solved the problem. I did not get a CEL with the problem so I also thought it was a tranny problem but not so.
Good Luck,

"Doc"

Doc, can you explain how putting Seafoam in the tank and intake knocks anything loose that might end up in the converter.

HemiFun05
 
#7 ·
No Rt-VA that's an excellent question that has puzzled me as well. Others have theorized that the old 360 was perhaps running rich anyway before the treatment and the raw gas caused increased temperatures which 'may have' began to melt-down the guts of the old 100+K catalytic converter and combining that with any deposits flushed by the fuel system treatment could (?) have been a contributing factor to the the converter becoming almost completely stopped up. All I can personally attest to is that prior to the fuel system treatment the old 5.9 seemed to have the same tranny symptoms mentioned in the original post and I serviced the tranny too thinking that would've been the cure but it was not. After replacing the defective converter and a tune up the truck ran fine and the tranny shifted correctly. Hopefully someone can shed more productive information on this subject - perhaps I was just lucky with my situation. Thanks.


"Doc"
HemiFun05
 
#8 ·
So I have been trying to replicate the symptoms but so far it has not had the shifting issues mainly at the lower speeds when you get on it. To answer the first question no the truck does not redline when this happens.

I like where the discussion has gone because it got me thinking today on the drive home that the truck was acting up at highway speeds and it felt like the motor was what was actually cutting out. I consider myself fair as far as being mechanically inclined but I'm at a lose here. I did a tune up about 40k ago and I might try to do one again soon. It might be important to note too that I use sea foam fairly often about every 6k or so but only in the gas tank. Don't know if that helps but I like the suggestions keep them coming and cross your fingers nothing catastrophic happens before this is solved. Thanks again y'all!
 
#9 ·
Sorry, got mixed up with terms. Talking about transmissions and then saying the Converter was clogged, thought you were refering to the Torque Converter. As for the catalytic converters they can breakdown from age, leaded fuel (racing fuels) oil burning and I suspect using SeaForm. I don't believe in magic elixlirs. On their website they state the formula is 65 years old and does not harm any of the engine systems. Even the leaded gas of 65 years ago would ruin a present day cat. Burning a petrolem base formula of the quanity and strength needed to breakdown and remove engine buildup would be in my opinion exceedly strong and probably not for sale over the counter to the general public. IMO, the only positive attribute SeaFoam might might have is to remove moisture from the fuel system. My 2 cents...
Back to the problem, have you rolled up your rpm holding second gear to see if the engine starts missing or hits a wall? Bad cats should choke the engine pretty consistantly around the same rpm. A fresh tune-up always is a good starting point. Also, the MAP sensor feeds input to the transmission indicating load. Possible bad connector, wire or sensor. Just thinking out loud... good luck..
 
#10 ·
So my truck finally threw a code P0300 random misfire. I guess you had it Doc! So y'all think a tune up will do the trick or maybe something more serious?
 
#11 ·
Hope you found the 'fix'!
Like I mentioned earlier a new catalytic converter and tune-up solved all of the same problems that you've described when my tranny started shifting poorly or not at all.

"Doc"
HemiFun05
 
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