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Does anyone know what might be causing this, when driving with over drive off the truck runs sweet as nut however once overdrive is on as soon as it hits fourth it starts behaving irraticlly it gets worse when hot, don't know if this may have any bearing but the exhaust has started blowing and the cruise control will no longer work. Strange coz one day it ran great and the next like ive explained. Can anyone help, hoping its not transmission. ��
 

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Does anyone know what might be causing this, when driving with over drive off the truck runs sweet as nut however once overdrive is on as soon as it hits fourth it starts behaving irraticlly it gets worse when hot, don't know if this may have any bearing but the exhaust has started blowing and the cruise control will no longer work. Strange coz one day it ran great and the next like ive explained. Can anyone help, hoping its not transmission. ��
You might want to be more detailed in your question. But if you are having a hard time shifting and staying in 4th gear you might want to just try check the 3-4 Accumulator Spring, they break often and cause odd 3-4 shifts. Of course it can be something else but lets just start with that because I can almost bet you have a broken spring.
 

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Sure sounds like a vacuum leak. You'll probably soon have a CEL which will point to a #8 cylinder misfire ( I don't know why, but thats the cylinder that takes the brunt of the abuse, at least in my truck)Pull the air cleaner housing, open up the throttle plates, and look into the manifold,with a flashlight. if theres oil in there, ANY oil, you are due for a gasket change to fix the vac leak. There is always the possibility of vacuum leaks elsewhere, take a look at, for example, the cruise control diaphagm beneath the battery, for example, Good luck!!!
 

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my truck is doin the same thing. i got the truck, and 30 min after i left the guys house the tranny went. he took it back and dropped another tranny into it. picked it up and ran great but about 30 min down the road it went out again. i hauled it home this time and found another tranny. i put this one in and after complete it ran great. shifted smooth and perfect. accelerated strong but havent drove more than 10 minutes until today. today i was heading to work and after almost 20 minutes, i was doing 55-60ish and all of a sudden the tranny starting bucking as ill call it like if it was popping out of gear and back in. so id ease off the gas and ease back in and it kept doing it. i pulled over and checked the fluid to find it full and clean still. looked under neath to find no crazy leaks or anything broke so i got back in and headed back home to switch cars. this time i turned off the overdrive and just drove under 55 to keep the rpms low and the tranny shifted perfect 1, 2, 3rd with no problem.....any advice or suggestions?
 

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I can't quote anything on the transmission unless I have more information, having a sluggish vehicle when the transmission goes to 4th can be something as simple as a fuel pump, in my case that's what it was then it progressively got worse. You could also have a slipping torque converter or yes vacuum leak.
 

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my truck is doin the same thing. i got the truck, and 30 min after i left the guys house the tranny went. he took it back and dropped another tranny into it. picked it up and ran great but about 30 min down the road it went out again. i hauled it home this time and found another tranny. i put this one in and after complete it ran great. shifted smooth and perfect. accelerated strong but havent drove more than 10 minutes until today. today i was heading to work and after almost 20 minutes, i was doing 55-60ish and all of a sudden the tranny starting bucking as ill call it like if it was popping out of gear and back in. so id ease off the gas and ease back in and it kept doing it. i pulled over and checked the fluid to find it full and clean still. looked under neath to find no crazy leaks or anything broke so i got back in and headed back home to switch cars. this time i turned off the overdrive and just drove under 55 to keep the rpms low and the tranny shifted perfect 1, 2, 3rd with no problem.....any advice or suggestions?
I got your other message I'm going to send those documents I have to you tonight. As far as what you describe it can actually be fuel pump related, sounds NUTS but it's very possible. As the speed and load increases the demand for fuel increases, if the pump cannot deliver fuel with the correct pressure 45PSI then you will practically start to stall out when it shifts to 4th, In my case I would start driving then once I reached about 75 when it shifts into 4th then it would just die, I thought it was the transmission so I rebuilt the transmission, their was a couple hardparts that needed replacing and I knew I would be towing often so it would be prudent to rebuild it. Well rebuilt it and then I was driving and the vehicle felt so under powered and it would have misfire's and then all of a sudden backfire. Well I was like ok the transmission I rebuilt it so that's off the list, then I said well 16 year old fuel pump and it was just pushing 35 PSI at idle and so I bought a new pump 129.99 Shipped, popped that puppy in their and not a single problem, I even can attest that I am getting slightly better MPG's nothing extreme but the needle is a little more merciful! Also rebuilding the transmission helped SO MUCH! Thing takes off like a rocket.

But back to your situation, just give a fuel pressure test a shot it wouldn't hurt. Their are certain parts that start to fail at certain ages, usually around 10-15 years expect to replace the fuel pump. Their is no age expectation for a transmission, I took mine out had a mear 126K miles the clutch packs were in perfect condition, I replaced them anyways. I had to rebuild my transmission sooner or later cause I cracked the bell housing.

Another thing that could be causing issues is a slipping torque converter but it's unlikely.
 

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I got your other message I'm going to send those documents I have to you tonight. As far as what you describe it can actually be fuel pump related, sounds NUTS but it's very possible. As the speed and load increases the demand for fuel increases, if the pump cannot deliver fuel with the correct pressure 45PSI then you will practically start to stall out when it shifts to 4th, In my case I would start driving then once I reached about 75 when it shifts into 4th then it would just die, I thought it was the transmission so I rebuilt the transmission, their was a couple hardparts that needed replacing and I knew I would be towing often so it would be prudent to rebuild it. Well rebuilt it and then I was driving and the vehicle felt so under powered and it would have misfire's and then all of a sudden backfire. Well I was like ok the transmission I rebuilt it so that's off the list, then I said well 16 year old fuel pump and it was just pushing 35 PSI at idle and so I bought a new pump 129.99 Shipped, popped that puppy in their and not a single problem, I even can attest that I am getting slightly better MPG's nothing extreme but the needle is a little more merciful! Also rebuilding the transmission helped SO MUCH! Thing takes off like a rocket.

But back to your situation, just give a fuel pressure test a shot it wouldn't hurt. Their are certain parts that start to fail at certain ages, usually around 10-15 years expect to replace the fuel pump. Their is no age expectation for a transmission, I took mine out had a mear 126K miles the clutch packs were in perfect condition, I replaced them anyways. I had to rebuild my transmission sooner or later cause I cracked the bell housing.

Another thing that could be causing issues is a slipping torque converter but it's unlikely.

first i got ur email with the manual...i saved to my phones SD card so i can plug into the computer...thanks a bunch...anyhow i will def look into all the suggestions u gave me(oil beneath the throttle plates, cruise control vacum - since my cruise stopped working too since i put this tranny in, and the fuel pressure). but i got this tranny used from a guy who claimed it was rebuilt and seem legit based on his knowledge and how he talked. so we put it in, filled it up and away we went. truck accelerated like a rocket with the monster 5.9L all the way up to 90mph. the over drive button wroked perfect with no delays turning it off/on. but i havent drove it more than 15 minutes until the other day when it starting ****in up. so i noticed it has to be warm or ran for a while b4 it acts up and like i said b4, the first two trannys that blew both blew in the first 30 minutes of driving which tells me its prolly more truck related and not tranny related. one other thing i dont no if i mentioned, is that the truck idles good but when i rev it up, it gives a "shudder like" vibration once it idles down(around 1000-1500rpm) and idles fine once under those rpms. thanks again for ur advice and suggestions, if u have any more, my ears are open. also if u have any ?'s about my trucks issues,
 

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first i got ur email with the manual...i saved to my phones SD card so i can plug into the computer...thanks a bunch...anyhow i will def look into all the suggestions u gave me(oil beneath the throttle plates, cruise control vacum - since my cruise stopped working too since i put this tranny in, and the fuel pressure). but i got this tranny used from a guy who claimed it was rebuilt and seem legit based on his knowledge and how he talked. so we put it in, filled it up and away we went. truck accelerated like a rocket with the monster 5.9L all the way up to 90mph. the over drive button wroked perfect with no delays turning it off/on. but i havent drove it more than 15 minutes until the other day when it starting ****in up. so i noticed it has to be warm or ran for a while b4 it acts up and like i said b4, the first two trannys that blew both blew in the first 30 minutes of driving which tells me its prolly more truck related and not tranny related. one other thing i dont no if i mentioned, is that the truck idles good but when i rev it up, it gives a "shudder like" vibration once it idles down(around 1000-1500rpm) and idles fine once under those rpms. thanks again for ur advice and suggestions, if u have any more, my ears are open. also if u have any ?'s about my trucks issues,
If you get a shudder like vibration at high rpm's when you rev it in idle it can be related to 2 things, 1 is a out of balance torque converter and the other thing is a bad fuel pump.

Some say when a fuel pump dies it just dies that's it, not true.
Fuels pumps in these dodge trucks around our vintage will actually begin to clog up and loose pressure, the fuel pumps had many metal parts that actually rust overtime and the rust particals clog the filters, when I removed my old fuel tank to replace the pump the gasoline was ORANGE and their were particals of metal in the bottom of the tank and the filter was BLACK and clogged. This pump caused me so many problems.

I was driving one day from SC to Florida, full tank of gass (35gallons) cruising 80MPH I-95 S. Then about 150 miles from my destination I had this stutter vibration and then a loud BAM, speed dropped out of the sky like a dead bird. I stopped at a gas station and I thought to myself the transmission must be dead. I had it parked idling and I revved the engine and it had a shudder well I sad ok torque converter is no good, I was able to drive it about 135 more miles before it died, I had a tow 18 miles (109 bucks). The next day I started it and it drove perfectly fine except it felt sluggish, then one person passed me and I floored it and once I hit 80 same thing happened bogged out, I thought ok OD unit is messed up need to rebuild it. So, I went ahead rebuilt the whole transmission, complete overhaul. During the rebuild the only thing that showed any clues to a faulty OD would be the OD Direct Clutch Hub's splines where all burred a broken 3-4 shift spring. Well I rebuilt it and upgraded it. Then I put the transmission in with a brand new torque converter. Well I took it for a drive, it felt sluggish and after maybe 25 minutes of driving it started to bog and misfire, so I took it home and said to myself it cannot be the transmission because I rebuilt it. So I did a fuel pressure test 35PSI at idle, seemed normal but I said I don't think so... So I bought a new fuel pump 129.99 shipped, took the tank out cleaned the inside and replaced the pump, gasket, filler tube grommet, mounting hardware. Filled it up and it ran like a champ, didn't feel sluggish one bit. After sometime of driving 400 miles I developed a horrible vibration and noise, so I said GREAT transmission, I remembered when I rebuilt the transmission that my rear planet had some slop in it so I bought a 6 pinion rear planet. I went down to FL and spent the weekend removing the transmission just to replace that one part which was a benefit because the new planet brought my total end play to .06" which is on the money for perfection. I also noticed that when I was preping the transmission for removal all my torque converter bolts were loose which explained the knocking like noise. Well I went ahead did all that work and the grinding noises went away. Only thing left is rear end vibrations and rumbling noise, the driveshaft is out of balance due to my part but I had planned to replace it. The axle bearings are probably shot causing the rumbling or carrier bearings but eitherway It's rear end related, my axle is also slightly bent but nothing a little chain, heat, and bottle jack won't fix.

But to the point all my problems were really cause of a faulty fuel pump. Thing is that many transmission like sympthoms can be a result of a fuel pump failure.

A healthy fuel pump really should be 40PSI or higher at idle not 35, all the documents that state 35PSI are wrong, I was idling 35PSI and was having problems. I replaced the pump 45PSI and no problems, but I'm not going to promise you this is your problem but it sure sounds like it.

I had replaced my U-Joints but they were seized in the yokes so I had to cut them out with a grinder, the grinder took some metal off the yokes and I also sanded a small piece of the driveshaft to check the depth of the pitting. This all cause a balance loss, but again I knew I was going to replace the driveshaft anyways because I needed something I can rely on. But it's driveable for now. The bearings are just a theory for me, But I'm confident that's causing my problem but enough about my problems. LOL

I would seriously check out the fuel systems, the cruise control loss can be a result of a broken vacuum line or a stuck check valve.
 

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RAMVAN!!! You got your stuff together , ain't no doubt, wish I had your trans experience, I don't have a clean enough, comfortable enough place to do that kind of work. OR the intestinal fortitude to rip my transmissions apart. Kudos to you!!!Fuel pumps cause ALL sorts of weird, unusual grief, I agree, the reason I have my 98 was cuz of fuel pump grief with my 95, many years ago.I almost junked it out because of fuel pressure. I am now a big believer in fuel pump pressure gauges. 45 and rock steady is the law around here.
 

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RAMVAN!!! You got your stuff together , ain't no doubt, wish I had your trans experience, I don't have a clean enough, comfortable enough place to do that kind of work. OR the intestinal fortitude to rip my transmissions apart. Kudos to you!!!Fuel pumps cause ALL sorts of weird, unusual grief, I agree, the reason I have my 98 was cuz of fuel pump grief with my 95, many years ago.I almost junked it out because of fuel pressure. I am now a big believer in fuel pump pressure gauges. 45 and rock steady is the law around here.

Thanks very much, so much information out their is misleading. All the source information states 35PSI, yet at 35PSI Isn't good enough. The law has been passed 45PSI!

I have not a doubt in my mind you or anybody can't rebuild a transmission, the torque flites are actually very easy to rebuild, the diagrams you see on the internet make you cringe but once you open one up you will actually realize the simplicity of the older TF's. It's just like swimming, you want to learn you got to get your feet wet.

I believe with the correct information and with practice anyone can do anything! That simple.

Oh, if you ever need another pump I got a great deal at www.highflowfuel.com

They offer a lifetime warranty and an amazing price.

(I still get excited having a working fuel gauge)
 
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