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95 k2500 suburban 7.4l 4l80e code 68.

Timothy Reyn

By Timothy Reyn
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Timothy Reyn New Member

Timothy Reyn

Posted
Posted

Okay so this has me a little stumped. It has a fairly fresh jasper trans, fresh fluid and filter, . Around 45 it starts to buck in a way basically trying to lock in tc and out if I am applying light gas, if the rpm is above 2300-2500 it is smooth as glass, get it up to about 60+ it doesnt do it at all just smooth sailing no matter how much gas you give her. I have functioning cruise control, I am not missing gears or experiencing any slippage else where nor any weird or delayed shifts. I have ran some lucas antislip stuff in it and seems to lighten a little but not much so I am trying to figure out if I should be hunting down sensors or saving for a good t.c. when I changed fluids theres no evidence of shavings in it other then the normal slight wear which the fluid before I changed it was honestly beyond gone as in looked like a century old motor oil with a red tint level gone but smelled like trans. Which trans acts just fine other then that 45+ areareceived_345006547032870.thumb.jpeg.acc17088af3cabcb332c3627da1b8769.jpeg

Timothy Reyn New Member

Timothy Reyn

Posted
  • Author
Posted
Just now, Supreme Pizza said:

Is that your transmission fluid? Or the creature that killed Tasha Yar on Star Trek The Next Generation?

 

 

 

 

 

 

118.jpg

Oh yeah was nasty stuff man. But like I said nothing in the pan other when just a wee bit of normal wear. No chunks no glittery shavings etc. It definitely had something go wrong either was abused, they cheaped out and reused fluid, or someone accidentally dumped some motor oil in it. Which next week im doing another clean out just to make sure I got everything that was left over. But im trying to get w feel on what else to do, im no tranny guy by any means but motors I know, just havent found much support with trouble shooting the code 

Supreme Pizza Senior Enthusiast

Supreme Pizza

Posted
Posted (edited)

It looks like the fluid is being burned. If you are just draining the pan, then you would need to:

 

Drain, Refill, Drive.

Drain, Refill, Drive.

Drain, Refill, Drive.

 

After 3 times you would probably have 60% new fluid.

 

The fluid condition indicates that your transmission may not be performing correctly, and the imminent failure is possible. Maybe the bad fluid is causing the problems, but probably not. Its worth a try though, replacing the fluid.

 

Drain plug trans pan would be worth installing, to save time.

Edited by Supreme Pizza
Timothy Reyn New Member

Timothy Reyn

Posted
  • Author
Posted
2 minutes ago, Supreme Pizza said:

It looks like the fluid is being burned. If you are just draining the pan, then you would need to:

 

Drain, Refill, Drive.

Drain, Refill, Drive.

Drain, Refill, Drive.

 

After 3 times you would probably have 60% new fluid.

 

The fluid condition indicates that your transmission may not be performing correctly, and the imminent failure is possible. Maybe the bad fluid is causing the problems, but probably not. Its worth a try though, replacing the fluid.

 

Drain plug trans pan would be worth installing, to save time.

Yeah ive already changed it one and a half times( yes half to drain and add lucas and some fresher fluid)  will be tanking it for a full system flush next week after the holidays. Which it was only that color when I first got this thing not that long ago, which I doubt it just fluid issue too hense why I am trying to get more ideas on where to start trouble shooting this thing as I have only found a single forum on it and their symptoms was not like mine

Jsdirt Senior Enthusiast

Jsdirt

Posted
Posted (edited)

Jasper has been sucking lately - lots of friends of mine have been dealing with comebacks left and right due to Jasper installs. Not sure what's going on over there, but they're not the company they used to be.

 

The transmission is JUNK - whoever installed it needs to warranty it. No question about it. Black is clutch material. It's toast. You dumping that mechanic in a can stuff might have screwed you, though - you could get denied when they tear that one down. That stuff makes the valve body gaskets, which normally peel right off, stick like glue to the valve body. It also swells seals up, making actuators and clutch assemblies extremely difficult to disassemble. As soon as they crack it open and smell that, you might be screwed. Hopefully a decent shop installed it. It was clearly built WRONG.

 

I know of 2 places - one in Amarillo, TX, and the other in eastern / central PA that built top-notch transmissions if you're close to either. Even if you're not, the PA one ships. The guys in TX don't like to ship their products out because so many people destroy them upon install. Have to know what you're doing. You can turn $5,000 into scrap instantly.

Edited by Jsdirt
Timothy Reyn New Member

Timothy Reyn

Posted
  • Author
Posted (edited)
13 hours ago, Jsdirt said:

Jasper has been sucking lately - lots of friends of mine have been dealing with comebacks left and right due to Jasper installs. Not sure what's going on over there, but they're not the company they used to be.

 

The transmission is JUNK - whoever installed it needs to warranty it. No question about it. Black is clutch material. It's toast. You dumping that mechanic in a can stuff might have screwed you, though - you could get denied when they tear that one down. That stuff makes the valve body gaskets, which normally peel right off, stick like glue to the valve body. It also swells seals up, making actuators and clutch assemblies extremely difficult to disassemble. As soon as they crack it open and smell that, you might be screwed. Hopefully a decent shop installed it. It was clearly built WRONG.

 

I know of 2 places - one in Amarillo, TX, and the other in eastern / central PA that built top-notch transmissions if you're close to either. Even if you're not, the PA one ships. The guys in TX don't like to ship their products out because so many people destroy them upon install. Have to know what you're doing. You can turn $5,000 into scrap instantly.

Trans was previously done before I got it and  I am only about $1900 in the vehicle total minus tires including buying and titling etc. So dont mind if trans is shot after all. But the weird part is its only in that one speed section at a low rpm thats what gets me.no other trans symptoms

 

Edited by Timothy Reyn
Jsdirt Senior Enthusiast

Jsdirt

Posted
Posted

Torque converter could've failed where it's not releasing from lockup. Or there's a short to power in the lockup wiring. I can only guess from here.

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