Been having some issues with my tranny. When cold it works great, all shifts are normal and no issues are there.

When hot, I have issues with the truck going into 3rd (I think it's 3rd). sometimes it goes in fine and sometimes it's like it go in, then jumps down and then back in, and then it's fine... Also, when these problems start happening, if I'm in town and come to a stop sign, it's like it doesn't always shift down into first. So when I start off, it's in 3rd, I think maybe second, and then the truck is kind of struggling until I give it a little more gas, and then it will down shift into 1st, and run thru all the gears again as if nothing happened... Again, this doesn't happen when it's cold. The other day it hopped between gears enough for it to throw a code. P0761, and P2702. I took a change and bought a new C Solenoid, fluid and fliter and I thought we were good to go on the test drive last night. Then when it got warmed up, it started acting up again like before... I just don't see it needed to be rebuilt because it only happens when fluid is up to operation temp. I also don't see that it needs to be rebuilt since it doesn't down shift to first gear at a stop sign everytime when fluid is warmed up. The only think that I can think of is that another solenoid is acting up, or a bad pump. SO basically what i'm down to is that there is a pressure issue, and when the fluid is cold with more viscosity then the pressure is higher causing everything to work correctly, an when it heats up, the pressure is less causing havoc... I don't know enough about trannys (yet) so any help is appreciated...

I"m pretty sure it's not the TCM as well. I have a tuner and at one point I could see all the PID's and could see what gear the tranny was in, but since I updated it a couple years ago, aparently now they stripped me of that PID with out paying more money... just found this out the other day, and I'm actually about to send an email to Spartan this morning, cause i'm a little heated about it. Regardless... Any info, I know there's a guy, Mark K. that helped build/tune, not sure if anybody else has knowledge or experience, Thanks.

 

It could be the tuner. Have you tried removing it to see if the problem clears up?

 

yes, that was the first thing that I did. No change. I just don't get why it's only acting up when fluid is warmed up... What exactly does each solenoid do, particular which solenoid has to do with which gear? Also, I ohmed out all solenoids when I was in there and all were with in range. 4.6/4.7 except the EPC solenoid I think. That one was 5.4 I believe which from what I found on line is all good, even the "C" solenoid, but I replaced it regardless since I had already ordered it due to the codes that were thrown.
I read in another post, that I think between 2-3, 2 solenoids act with in .03 seconds or something like that to make 3rd gear... I read it and now I cant find it again, so that may not be entirely correct, just wondering if there is another solenoid that I could replace.

 

In first gear you have the low/reverse clutch (SSE) applied. It drops off at about 5 MPH. The forward clutch is applied without using a solenoid.
Second gear adds the overdrive clutch, SSB.
For third gear SSB has to drop the overdrive clutch while SSC adds the intermediate clutch. Those two have to complete what they are doing within 0.030 seconds of each other or the shift is poor. If the overdrive drops off before the intermediate has capacity the trans goes back to first gear, then as the intermediate applies it shifts 1-3. If the intermediate gets capacity before the overdrive drops off you make a 2-4 shift, followed by a 4-3 shift.
To go to direct (5th gear) the intermediate has to release while the direct clutch applies (SSD.) The same timing requirements happen here. If the intermediate releases before the direct has capacity the trans does a 3-1-5. This will kill it. If the direct gets capacity before the intermediate releases you get a tie up. A tie up is where all parts of the rotating assembly are held, causing the output shaft to stop turning RIGHT NOW. If it stops turning, the wheels stop turning, too. Imagine that happening in the middle of a shift.
To get from 5th to overdrive the overdrive clutch comes on again, controlled by SSB. There is no timing requirement on this shift.



Each of the SSX solenoids directly control the pressure to it's respective clutch. The solenoid is what makes the clutch apply or release.

 

thanks for the info, had to read it a few times, to better understand, still reading it... so... so it seems that since I have yet to see an issue with 5th or over drive, that the SSC solenoid probably wasn't the issue. Possibly the SSB or SSE solenoids could be acting up. I would think they would act up when fluid is cold versus warm...

For 2nd both SSE and SSB or applied correct?

so when in 3rd and I come to a stop, in order to get back into 1st gear, SSC needs to drop, SSB is applied for 2nd, and then SSB is dropped leaving only SSE applied.

when you say SSx is "added" for 2nd, does this mean that SSE is still applied?

On a side note, I also should mention that during my test drive yesterday, I was doing 35 or so, and slowed to around 8mph to make a slight turn on a green. when I got back into it, I had no gear, I throttled the pedal 3 times before I felt the gear engage, and then I was back on my way. about a mile down the road I felt down shifting at a steady speed around 30 mpg. Wrench light came on, and codes were the same as listed above. when I came to stop and took off again, i was limited to 2nd gear. Got home, turned off truck, cleared codes, test drove around the block, and gears acted up again, I got home before allowing it to throw the codes again.

 

I just realized that I mis-read, So the SSE drops off at 5mph. then the SSB is applied for 2nd, SSB drops and SSC is applied within .03 to make third. I think there down shift to when slowing, and up shift when accelerating is having to do with the SSB and SSC, it makes sense. And when the hunting for a gear happens, it's probably that the SSB didn't do what it was supposed to, so I'm stuck in a gear, when I give it gas and go going around 5mph, it makes the shift down to 1st finally, and then to 3rd... this does make sense to what i'm experience... now the issue is, what is causing it ..? Granted the Solenoids ohmed out correctly, but could they still be bad? all harness seemed fine... again, whats throwing me off is that it does it when warm, and not cold.. erg...

 

What does the harness seems fine mean? Most problems that seem to be the solenoids are really a short/open/corroded connection in the wiring harness.

A problem that shows up warm but not cold could also be worn out seals in the clutches. The seals work better with cold, thicker fluid.

 

I must say,

Mark has absolutely been the/thee highlight of several forums involving the stroker's.

His advise and intricate knowledge of the most complex units on our daily travelers has been an ultimate blessing for anyone that had questions or urgent necessity.

He has first hand knowledge and more importantly, he helped engineer/build/refine them.

To give up a night of football, hockey or fishing to help everyone nationwide with tutorials and band-aids (stuck on the road what do I do) is exemplary!

Proud to be here and more importantly, proud to be in an arena with this class of staff.

Denny

 

sorry I didn't mean to leave you hanging... been busy... I guess it could be seals...makes sense for sure
.. just weird that it popped up out of no where and hasn't gone away... harness is fine from what I can see... is it possible to trouble shoot harness for short or ground? Ride now the under carriage is covered in mud... maybe it's causing in issue? But still doesn't add up as to why it does it when warm and not cold... thanks for all the help by the way!

 

How do the pressure solenoid work? I'm not convinced that the tranny had bad seals, or possibly something else requiring a rebuild. I have trouble thru out the whole tranny. I think I even use 4th gear when it starts acting up... when I come to a stop, it doesn't down shift to first gear.. and sometimes when it does, it will start off in first, then go to 3rd maybe then back down to 1st and be fine... I just don't understand whats going on... help is appreciated.

 

The pressure solenoids work by increasing or decreasing the pressure sent to the clutches based on signals from the PCM. That pressure is used to apply or release clutches to create different ratios inside the transmission.

I've never seen a harness work cold but not warm. I can't say that this is impossible, but I haven't seen it happen and I've been working with wiring like this since 1982.

It would be worthwhile to eliminate the Spartan as a source of the problem. Remove the tuner and see if the problem remains.

You can troubleshoot the harness. Disconnect the harness at the PCM and at the transmission. Probe the BACK of the connectors, NEVER put a probe in the end of the connector that makes the connection. That will cause new problems in addition to the one you're already trying to solve.

Check each wire for continuity, short to ground, and short to power.

 

Do you think that a bad pressure solenoid could be an issue? I'm agree that it doesn't make sense with the acting up after being warmed up, however, some times it does do it when cold, also, when it warms up and it asks up, sometimes I have to pull off and turn the engine off, open the door so battery power goes off, and then restart, and it's fine again until it starts acting up again... The other day, it even tried to shift, and wouldn't go into gear at all, like it was in neutral, was able to pull off luckily, shut the motor off, and restarted, and it was fine... I don't know a lot about tranny's per say, but I would think if it were something mechanical, it wouldn't be an intermittent issue, atleast not what I'm experiencing... also, if it was bad seals, shouldn't it be effect those particular gears, and not effect shifting to 1st at a stop sign? Thats where i"m stumped, and unconvinced that it's a seal issue... In my opinion, it seems to be a pressure issue, or maybe a pump issue being that when the fluid is warmed up, the pressure is less due to viscosity change from temp... Maybe i'm just making stuff up cause i'm ill educated on tranny's....

 

Battery power to the PCM does not go off when the door is opened.

No. If the PCM detects a gear isn't working, such as would happen with a bad seal, it will stop commanding that gear until the next time the engine is started.

Then we agree. I think it is a pressure issue, too.

That's also possible, but in my experience pump issues are a lot less common than seal issues.

I've offered all the help that I know how to do. I have nothing further to offer.

 

I appreciate your help and time, Mark. Is there a wiring diagram out there that will tell me which pins on the connector TCM are for which solenoid harnesses? I'm going to trouble shoot wiring, hoping to get lucky and find something wrong. Probably going to replace pressure solenoid while i'm in there just so I can eliminate that as well... Could the TCM have an issue? I know nothing about TCM's except their purpose... Thanks in advance...

 

countryboy73703 did you get yours resolved? My 08 is doing the exact same thing! Would love to know what you found!