SureTrack Community Fix: Haunted Shifter

Real Fixes from Mitchell 1’s SureTrack® expert information resource are documented issues from actual shop repair orders and community discussions. Read on to see how SureTrack can help you correct issues that are not easily diagnosed using OEM information alone. SureTrack is available at no additional cost in our ProDemand product.


Would it creep you out if you’re driving along and your automatic transmission shifter decides to move to neutral on its own? SureTrack community member kamesautomotive had a Chevy Express van in their shop that did this but they knew it wasn’t haunted but wasn’t sure what the cause was. They posed the question to the community, and with the help of fellow community member trannyman1 and others, they were able to resolve the issue quickly.

The following Community Fix summarizes the interaction between members of the community that led to the solution.

Vehicle
2006 Chevrolet Chevy Express G3500 6.0L

Title
Shifter moves to neutral while driving, replace filter in valve body.

Complaint
Customer complains that shifter moves to neutral while driving. They have to hold it in drive to keep going.

Diagnostic Steps Performed/Parts Replaced
Test drove vehicle and confirmed that shifter is moving to neutral while driving. Found that fluid pressure is pushing the shifter into neutral. Dropped the body, looking for broken spring, bad gasket. Something that may be causing fluid pressure pushing against main valve causing it to move into neutral. Has anyone seen this symptom. Any suggestions?

Best Answer from Community Member trannyman1
There is a plastic filter behind manual valve that’s held in with a roll pin. Check it, if it breaks, it will push manual valve forward and do what yours is doing. That screen can also cause 2nd gear starts and no line rise, so make sure nothing is burned when you get it back together. I’ve never seen a reason for it breaking, other than it’s cheap plastic. I think either Transgo or Superior shift kits come with something to address the issue. It’s such a rare occurrence that the screen breaks, that we just install new and have never had a warranty claim over the new one breaking. Good luck.

Cause
Original issue was broken plastic filter. Since they drove it around holding the shifter in drive, the fluid was burnt. I did do the repair to the filter anyway to see if it fixed the issue. After repairs I discovered the 4th gear clutches are burned up. Bummer, needs a rebuild. Again Thank you for your help!

Correction
Replaced broken filter in valve body along with rebuilding transmission.


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About the Author

Nick Taylor

Nick Taylor is the SureTrack Community Administrator and a Senior Applications Specialist at Mitchell 1 with over 25 years of experience with electronic repair data systems. Nick previously worked in the automotive dismantling and engine rebuilding industries.