Reverse out on 2004 Chevrolet Silverado 2500

SOURCE: 2003 silverado chevvy 2500 HD

Automatic trans? Sounds to me like the trans is either busted up or damaged in such a way that the gearing won't rotate or things are binding internally. With the drive shaft off, transfercase in 2WD, and trans in anything but PARK, the driveshaft should be able to turn by hand. Of, course, a drop of the pan can also give a indication. When gears bust up in a 4L80E, there is evidence.

Harvey N Tawatao

• 3854 Answers
• Posted on Jun 23, 2009

SOURCE: 1997 chevy blazer 4*4 will not go into reverse

You may have a bad revers solenoid. Check the fuse and look for any of the fuse to be bad like the transmission fuse. Best thing to do is get the blazer scanned at Auto Zone free of charge for any DTC codes that may be affecting your transmission's performance. Try this, place the ignition to the run position and pull the ECM(BATT) fuse out for 30 seconds and then place it back in. Start the Blazer, it may stall but let it. Just start it again the ECM is just relearning the engine and transmission, let it idle for 1 min and then go for a test drive. This should reset everything in the truck's ECM like the day it was first started and any DTC code will be new and active. Do not add any additives like lucas transmission fluid repair, that will just make it worst. Any additive that may the transmission thicker will make the fluid retention more making the shift solenoid stick causing shift conflicts. Good luck and keep me posted. No revers is ether a bad solenoid, bad PCM signal, or broken sun gear. 

Roy Funkhouser

• 140 Answers
• Posted on Aug 10, 2009

SOURCE: Reverse Gear is Sluggish and makes noise.

I would say you should re check if you have 2nd and 4th. If not you need to have the sun shell replaced in the transmission. this is a comon problem. I hope this helps.
Thank You,
Roy

SOURCE: no reverse all of a sudden

check power to the reverse shift solinoid

Harvey N Tawatao

• 3854 Answers
• Posted on Jan 02, 2010

SOURCE: 2004 silverado tranny acting up starting w/ 2nd

Before guessing at transmission problems, check the fluid level (car warmed up, engine running in Park on level ground) and have the PCM scanned for trouble codes FIRST.

Also note that many problems that show up as transmission issues are actually PCM or electrical, and may be external to the transmission.

Secondly, put a line pressure gauge ($55 shipped on Ebay, or visit a local trans shop) on the pressure test port and go for a drive to verify proper line pressure. Base pressure at idle in P,N,OD should be around 70psi and around 140psi in R. Max line pressure should be at least 190psi at WOT in 1st or 2nd, 225psi is optimum. If base pressure is low, trans or pump is worn out. If max pressure is low, check EPC solenoid. If reverse is slow to engage, and line pressure does not come up to at least 130psi in reverse, replace the boost valve with a Transgo 0.500" boost valve (easy fix in pan).

1-2 shift does not happen at WOT until you let off the gas: Best case: try replacing the TPS. Middle case: leak in the 2nd gear apply circuit (servo assembly or 1-2 accumulator). Double check by using the pressure gauge and watch for a big drop when the PCM commands 2nd gear. Worst case: poor line pressure rise.

1-2 Shift shudder at WOT; delayed or abnormal 1-2 shift; There's a problem ONLY on the 1-2 shift: 1-2 accumulator piston cracked or stuck cocked in the bore. Check the yellow spring inside the accumulator housing for breakage. Also, if the accumulator housing walls are scored, the housing must be replaced. Easy fix in the pan.

1-2 shift is delayed and harsh, may not shift into OD: Check TPS for smooth and linear electrical response over the entire range of motion. If not, replace.

Soft shifting, gradual performance degradation: Poor line pressure rise due to leaking boost valve, clogged EPC filter screen, failing EPC solenoid, or worst case: leaky seals throughout. Transgo HD2-C kit fixes first two without removing trans. Seal restorer may fix last problem, but probably R&R. Also try a transmission flush with BG brand products (Firestone stocks it).

Here are the common things that may be happening to your transmission to what you have described. As for your transmission fluid being burn, that is a sign that your transmission is slipping. Your going to have to service the transmission again fluid and filter changed. Since your doing that you may want to replace the boost valve and shift servo. I did mine on my 4L60E and have over 365,000 miles so far, replacing the boost valve every 60,000 mile and it's only $45.00 and take less the 5 min to replace and the servo is around the same price. I did do the upgrade and have the corvette boost valve and servo in my transmission which helps a lot. The other thing to is B&M has a electronic shift controlled modulator you can install your self which would give you 3 settings and works great with the upgrades mentioned above.

Good luck and hope this helps, keep me posted and try not to run the transmission too long with the burnt and dirty fluid. The dirt in the fluid will cause the electronic pressure control (EPC) valve to fail and will end up causing a $2,300.00 total transmission rebuilt over a simple $190.00 up grade and maintenance.