Jmod trans rebuild need retune?

[stevengerard]

So my trans is rebuilt with heavy duty Art Carr parts and the Jmod was done. Occasionally my OD light goes mostly after long drives. The trans guys say it needs to be re-tuned to handle the higher pressures. I got the code and its P1783. Anyone know anything about the code or if I need to re-tune the trans

[RubberCtyRauder]

P1783 is Transmission over temperature condition which I got from here

http://motorcitymarauders.com/forums/showthread.php?t=6638

[Bradley G]

If your trans temps run higher than 180*, use an aftermarket trans cooler in addition to the minuscule cooler that the car has from the factory.

[Krytin]

The transmission should not overheat just from a long drive. Sounds like somethings slipping.

[stevengerard]

crud that does not sound good. It came on at the end of a drive last night too. I hope there is no damage done to the new tranny - I do not feel any slipping at all. I have only put on 100 miles or so

[whitey]

Check the fluid for color and the level

[stevengerard]

its full, almost clear its so clean, fluid is fine.

[ctrlraven]

its full, almost clear its so clean, fluid is fine.
Clear as in bright cherry red or clear as in colorless? I had a heavy duty trans cooler installed about 40-50k miles after I had my PI 3500 installed. Besides the converter, Jmod and a few other small upgrade pieces in the valvebody my trans is stock with 180k+ miles on it. Highest temp I have ever seen was 171 after pushing it hard during a hot summer day.

When I had my Jmod done I backed my tune shift pressure down to 5% on all shifts, anything higher seemed too harsh.

[Bradley G]

probably not, but I don't like it when shops only fix the symptom and neglect to prevent the cause of the issue.
My friend that has Rider90s' old trilogy car # 118? at 64K has had several trans issues(failures) and I still spy no extra cooler behind the grill.
Not to boast but I have several hundreds of passes at the drag strip and six sets of rears gone through.
He on the other hand has never been to the race track with it.
And Rider 90 never took a pass down the 1320 that I'm aware of.

I've had no tranny issues(except minor tailshaft seep)at 127K miles I just knew if I kept driving it , I would fail because my trans temps were high.
It took me over a year to get all the parts together and justify the most expense since the repaint and the blower.
My build consisted of the following;Trans Star overhaul complete kit,
BOC Triple plate custom convertor 3600-3800 stall, 40,000K transmission cooler, tailshaft forced lube mod, J -mod W/ softer accum springs,several other transmission upgrades ie;reinforce seperator plate for 1-2 accum. new sun drum, OD band HD. and a bunch of little parts he supplied that was all on display on delivery, including my old ,tired ,slipping ,stock convertor .
that reminds me I have not dataloged temps since the rebuild I was 205* with no hard driving prior to the surgury.



crud that does not sound good. It came on at the end of a drive last night too. I hope there is no damage done to the new tranny. I have only put on 100 miles or so

[stevengerard]

Clear as in bright cherry red or clear as in colorless? I had a heavy duty trans cooler installed about 40-50k miles after I had my PI 3500 installed. Besides the converter, Jmod and a few other small upgrade pieces in the valvebody my trans is stock with 180k+ miles on it. Highest temp I have ever seen was 171 after pushing it hard during a hot summer day.

When I had my Jmod done I backed my tune shift pressure down to 5% on all shifts, anything higher seemed too harsh.

surprisingly closer to clear - I thought is would be more red

[ctrlraven]

surprisingly closer to clear - I thought is would be more red

Ugh that could be your problem right there! Our trans uses Mercon V which is a bright cherry red color like this.
http://www.allfordmustangs.com/forums/attachments/2005-2010-mustang-gt-tech/39809d1203122713-deep-transmission-pan-2005-mustang-gt-trans_pan-011.jpg

[stevengerard]

I'll check that out again. You would think they would know that. It looked light, almost a yellow clear so that did make me wonder. They put a plug in the trans pad so if needed the job will be easy.

[ctrlraven]

I'll check that out again. You would think they would know that. It looked light, almost a yellow clear so that did make me wonder. They put a plug in the trans pad so if needed the job will be easy.

If it has the wrong fluid in it, the wrong stuff will have to be completely cleaned out, draining from the trans pan will only drain 3-5 quarts.

[Ozark Marauder]

http://i.ebayimg.com/t/Jetsons-Astro-Ruh-Roh-Magnet-/12/!B9-OsNgEGk~$(KGrHqZ,!hQEzek4CD5WB M7U55eehQ~~_35.JPG





OZ http://http://i.ebayimg.com/t/Jetsons-Astro-Ruh-Roh-Magnet-/12/!B9-OsNgEGk~$(KGrHqZ,!hQEzek4CD5WB M7U55eehQ~~_35.JPG

[Curless]

The code definition also states "increased EPC pressure", this has to do with your line pressures as well. I would always run a temp gauge on a "built" car's trans. The fluid should definitely be bright red. Clear or yellowish always meant burnt when I worked at a trans shop.

http://www.motoralldata.com/alldata/MOTOR%7EV116243060%7EC37591%7E R0%7EOB0%7EP4R0H%7EN/0/89012112/94698271/94698276/94698278/34853741/96340231/96340248/176614763/171362390/181486395

[stevengerard]

Thanks Chris, that makes me feel a little better - that's what they said its the pressure increase throwing the code. But that says the pressure is the symptom of high temps so I will see if I can get a temp gauge hooked up even to the ODBC temporarily - and I will check the color of the fluid again today.

[tbone]

Think of the trans fluid as a friction material, like sandpaper. If you have the wrong friction grade in there, it will slip, and overheat. I can't believe your shop could make that mistake.

[Curless]

Thanks Chris, that makes me feel a little better - that's what they said its the pressure increase throwing the code. But that says the pressure is the symptom of high temps so I will see if I can get a temp gauge hooked up even to the ODBC temporarily - and I will check the color of the fluid again today.


Yep, if the trans sees high temps it will increase the pressure to try to get it to stop slipping. You need a gauge and you need to make sure they used the right fluid.

[stevengerard]

they used the correct fluid, it looked and smelled correct to me. I asked my mechanic to check it out and he agreed. I then called the trans shop. he did replace a spring that came with the Art Carr kit and he said it definitely helped the shifting. he was very impressed with the car but is concerned why the temp is reading hi. He mentioned as you have to try to get a temp reading even using a thermal gun which I have.

He also mentioned that he only took the car up to 55 MPH and he noticed there was no lockup - I believe mine is programmed for 65mph. He said that is way too high for a car mostly driven around the neighborhood and in traffic. With a 3500 stall a lot of heat will be built up with such a high lockup. I hope I'm repeating that correctly.

[Curless]

they used the correct fluid, it looked and smelled correct to me. I ask my mechanic to check it out and he agreed. I then called the trans shop. he did replace a spring that came with the Art Carr hit and he said it definitely helped the shifting. he was very impressed with the car but is concerned why the temp is reading hi. He mentioned as you have to try to get a temp reading even using a thermal gun which I have.

He also mentioned that he only took the car up to 55 MPH and he noticed there was no lockup - I believe mine is programmed for 65mph. He said that is way too high for a car mostly driven around the neighborhood and in traffic. With a 3500 stall a lot of heat will be built up with such a high lockup. I hope I'm repeating that correctly.

This is possible, I would not want my lock up to come in that high. I would say that the lock up should come in anytime after it shifts into O.D. and then at lighter load. I am not sure of the protocol that has be written into your tune but it can be altered I am sure.

Get yourself a temp gauge and be sure that the temp is around 160-180, I run a trans braked, NO2 drag car and I like my trans at least 140 before I beat on it. You do not want it over 220 for long life though. By the way, my trans held up to more than 10 years of street strip abuse. Some say its luck, I say its knowing the temp and maintaining the fluid and filter.

[Marauderjack]

Just curious......wonder what temperature throws that code??:confused:

I would definitely lower the lockup speed to the mid 40's in 4th gear only.....3500 stall speed makes a BUNCH of heat!!:eek:

Good Luck!!:beer:

[stevengerard]

Just curious......wonder what temperature throws that code??:confused:

I would definitely lower the lockup speed to the mid 40's in 4th gear only.....3500 stall speed makes a BUNCH of heat!!:eek:

Good Luck!!:beer:

Ok, good to know - according to what Chis posted the table mentions 270 F

[ctrlraven]

Just curious......wonder what temperature throws that code??:confused:

I would definitely lower the lockup speed to the mid 40's in 4th gear only.....3500 stall speed makes a BUNCH of heat!!:eek:

Good Luck!!:beer:
My 3500 stall locks up at 47 mph in 3rd gear.

[stevengerard]

I dorve a buddy to the airport yesterday in Chicago traffic and the light started blinking. I'm bringing it back to the shop. I just don't trust it. Someone mentioned that the Jmod along with the art carr kit may just make too much pressure. But I would think you could change that with tuning as well.

[stevengerard]

Light went off again, I used a thermal sensor gun to check temps. Pan was 180 - 185 all over. Out going fluid line was 187 incoming was 180. I took out the trans dipstick and measured the end it was 104. So looks like the temperature is ok. I would doubt that the trans would cool off from 270 or higher (the temp the code gets thrown) down to 180 that quickly.

[tbone]

Definitley lower that lockup to low to mid 40's anyway.

[Curless]

Light went off again, I used a thermal sensor gun to check temps. Pan was 180 - 185 all over. Out going fluid line was 187 incoming was 180. I took out the trans dipstick and measured the end it was 104. So looks like the temperature is ok. I would doubt that the trans would cool off from 270 or higher (the temp the code gets thrown) down to 180 that quickly.

Smart thinkin on the temp gun! Good to know that the trans is not overheating. Now get that tune checked out!

[screamn]

Maybe just try revert back to stock and see if that solves the above issue. Then take it from there with adjusting line pressure or lockup.