The Top DSM Community on the Web

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. Log in to remove most ads.

Please Support STM Tuned
Please Support ExtremePSI

Auto slipping when in D or in reverse

This site may earn a commission from merchant
affiliate links, including eBay, Amazon, and others.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

UrN2nd

15+ Year Contributor
75
0
Mar 13, 2008
friendsville, Tennessee
I did a trans service a few weeks ago. Took the car out for numerous test drives. Test drove it to the shop about 30 miles no issues. Tuning the car now so past week it's been up the road and back. Yesterday it started acting up. When in park it's fine when I shift it into drive or reverse I let the brake pedal go and it acts like it's in neutral. I give it a little gas and it clunks into gear. As I back up it slips out of gear revs for sec then clunks back into gear. Fluid is full new filter was put in a few weeks ago and I put the royal purple ATF and the black lube guard in it. Don't know what's wrong
 
What exactly did the Trans servie consist of? Could be a few things....incorrect amount of fluid, bad solenoids, bad tcu, etc... Are you throwing any codes transmission related?
 
Check to see if the trans fluid filter has been broken or is not sealing correctly. This will cause the pump to potentially suck in air and cause what you are experiencing. Also What filter did you use? OEM should be the only one going on there. It sounds like a line pressure issue. Double check the fluid level and check that filter out, then report back.
 
May I ask why you used Royal Purple ATF? Instead of normal ATF or Redline fluid?

How much fluid did you put in the car? What all did you service/remove?
 
I used the royal purple bc I read a thread on here that said it was the best to use besides oem mitsu fluid. The service was I had the trans out bc I was rebuilding the motor. I changed the filter with a O'Riellys purchased one. Flushed the trans out cleaned it, painted it. Refilled with fluid and lg additive. And it ran perfect till yesterday. After I get going it runs fine shifts fine it's just acting up in 1st gear and reverse. If I put it in '2' it pulls and drives fine from a dead stop. But if I put it in 'D' it slips when I'm giving it gas until I start moving then it's fine. But when I come to a stop it downshifts fine till it shifts into 1st then it has a slight clunk.
 
Can't remember but I was a quart low after a few test drives so I added a quart of +4 and a tiny bit more lubegaurd
 
Can't remember but I was a quart low after a few test drives so I added a quart of +4 and a tiny bit more lubegaurd

These tranny's are very sensitive. It is crucial that you put the correct amount of fluid in. The fact that you can't remember, and you took apart the entire transmission is not a good. Should have been 11 quarts.
 
I didn't take it all apart just cleaned everything. I had 2 cases of fluid. I filled it and then test drove it then had to add a lil more. it is full as of now. it drove perfect until a few days ago. ive checked the fluid level multiple times and its completely full.

is there a linkage adjustment maybe its holding it a tiny bit out of gear. it feels like its in neutral and revs but grabs and jerks then sits in neutral for a second and revs the jerks into gear. after I get moving it runs perfectly fine.
 
There is a lever adjustment directly on top of the transmission. Two cases of fluid? I think one case is 11 or 12. How are you checking the fluid? while the car is running in neutral at operating temperature?
 
She likes when I slip in the D.


On a serious note. I'd turn up the line pressures, I'm wondering if you burned the clutches a bit tuning.
 
How do I turn up the line pressure. I had 2 cases I used it on 3 different cars.. I get it up to op temp then check it with trans in neutral
 
How do I turn up the line pressure. I had 2 cases I used it on 3 different cars.. I get it up to op temp then check it with trans in neutral

To turn up line pressure you have at least 3 options. You can chip the tcu (I did this as it was easiest for me since I DD this car)

or Blue Wire Mod

or Shift box.

As far as it still slipping, it could be the clutches are worn out. How many miles? Also could be the tranny pump going bad. My car was experiencing shifting and clunking into gear when the tranny pump was leaking.

Rebuilt the tranny back in August and have had zero issues.
 
You shouldn't need to modify anything. IF the trans is slipping than there is an internal problem. Turning up the pressure is only a bandaid for this. I would before anything drain that royal purple and put some +4 back in it and see if it helps. Most likely you have burnt clutch packs though.
 
Ok so what's the exact fluid I should put in it? I'll have a transfer machine do it so it changes the torque converter as well. And how man quarts
 
Does the idle switch talk to the trans at all?
 
Support Vendors who Support the DSM Community
Boosted Fabrication ECM Tuning ExtremePSI Fuel Injector Clinic Innovation Products Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications MyMitsubishiStore.com RixRacing RockAuto RTM Racing STM Tuned

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds

Back
Top