Now before I get flagged I’ve been going through and reading the E4OD threads and I haven’t found much info on this problem.

So I’m having code 628 Excessive converter clutch slippage and I’m honestly not to sure on what hat really means. I read something about it being a bad solenoid pack but I couldn’t find a concrete answer.

Heres the symptoms
hard shift all gears
shifting into reverse it hits really hard
clear the code and the transmission shifts like a dream
has taken 50-500 miles before the hard shifts come back.

What ive done
full fluid change including torque converter and cooler
new filter
lucas transmission additive.

So what ya think my issue is?

 

In summary,it simply means the computer has sensed that the converter has unlocked,under conditions when it shouldn't have.
That code by itself however,leaves you hanging to figure out why.
9.9 times out of 10 an electrical issue has caused the converter to unlock,rather than an actual mechanical failure being the cause.

The hard shifts are not the fault per say of this code alone but the default safety programming the PCM goes to,when it's senses a code and causes the OD cancel light to flash.These firm shifts don't in any way indicate a bigger problem.The reason why the firm shifts go away after clearing the code is because it longer has the memory of the stored code and doesn't know yet,until driven again (it takes a few times for the PCM to sense the issue) that it needs to go into limp mode.

Though there can be several reasons for the converter slip code,very often a dirty/faulty connection at the bulkhead is the issue and always the best place to start.

Click here:
E40D: The Importance Of A Clean Trans Harness

Though the slip code for those trucks is a simple two digit 62 code,the same info applies.

 

thanks I will definitely check out that plug and add dielectric grease.

Im just hoping is a simple fix.

 

You might want to look at the plug on the right side of the transmission, for the solenoid pack. It points up from the case, near the rear edge of the pan. You will have to remove a metal heat shield to get to it.

IF that plug is wet with transmission fluid, you'll need to replace the solenoid pack. The seal in the plug breaks down, lets fluid iinto that area around the pins and causes malfunctions like you're experiencing.

 

Take a look at the front of the torque converter. You'll have to remove the dust shield on the bellhousing to see it. Almost certainly the front of the converter has some blueing, similar to what you'd see on a blued steel pistol. That indicates that the converter has been slipping. That is caused by a crack in the torque converter clutch apply piston. That bleeds of pressure and allows the converter to slip. The only fix is a new torque converter.

 

These harnesses are very well known for falling apart, its a very thin gauge wire. my brother had to completely rewire his BE CAREFUL

 

Well I cleaned up the harness connector, had some fluid in side.

I also ran a torque converter test and it kickes in at 2k with no slippage. I’m also getting some torque shutter at 40-45mph.

So so now the question: to change the converter or the solenoid pack?

 

Also my OD light has never flashed during this whole ordeal

 

Can you describe this test that you ran? I have no idea what this means.

 

If you have ATF down inside the solenoid pack connector,then you'll need to replace the pack,no matter what you do,short of replacing the whole trans so you can safely replace that and see what happens.You can get remans on ebay.

 

it’s especially a brake stand. Mash brake to the floor and see what RPMs tires spin at. It kicked in right at 2k.

 

ok will do then go from there. Thanks, I kind of needed a nail in the coffin

 

heres where i got the idea from

Torque Converter Problems: Signs, Causes, & Replacement

 

That checks stall speed. It has nothing to do with the torque converter clutch, so it can't detect if the clutch is slipping or not.

I recommend you try this:

 

thanks Ive never really worked on transmissions so it’s a steep learning curve for me