2002 Z71 Transmission

[bcoker]

Can anyone recommend what I should do? I have a 2002 1500 Silverado Z71 that has 50k miles. The transmission continues to shift hard even after having the fluids changed a few months ago. I have taken it to a mechanic and was told that it is normal, however he only drove it a few blocks and I dont feel he got the full effect. I have a 21 foot boat that when pulled the transmission shifts so hard I swear at times I can hear the tires sqeal. It does not do it that hard just driving empty so it is hard for me to get a mechanic to realize what I am talking about. I appreciate anyones advise.

[TXAGG05]

I have the same truck and pull a similar boat. I can't say I've noticed any different shifting while pulling the trailer, but it does shift pretty hard without it. My roommate's truck shifts really firmly and his father is a mechanic and says it's better that it shift hard, thinks it will last longer. Makes sense to me because I figure it's more direct gear to gear.
Jeb
Oh,...does it do it all the time or just when hot or cold?

[AaronIROCZ]

when the any automatic trans shifts feel soft it is actually slipping the clutches and gradually engaging, where as the firmer shifting trans does not slip them as much if at all so there is less heat and less wear on the clutches, thats why it is better for them to shift firm

[bcoker]

that all makes sense, however one thing I forgot to mention is that there is long pause from when it shifts out of first and hard into second, do you think the pause causes the engine to rev slightly which makes it hit second hard? it does this all the time hot or cold, maybe I just notice it more when pulling the boat because I am pushing it harder

[Ape0r]

The harder it shifts, the longer your cluthes will last, and the longer it'll be before you have to get the transmission rebuilt, if you plan on keeping it that long. IMHO, don't worry about it. If it is going to break, run it until it does and save yourself some time. If it isn't, then it won't!

[desertmike1]

bcoker,
I had a very simular situation with my 99, as it turned out to be the Tranny was actually shifting from 1st to 3rd gear, my 2nd gear was missing all-together.

Symptom: dead stop to 3rd gear at approx 20mph accompanied by higher engine RPM and a hard shift.

Cause: Chevy installed a 2nd gear accumalator piston made from plastic reson material that had cracked. Allowing a drop in hydraulic pressure in the #2 circuit which ultamatly burned clutch's in my reaction pack and damaged a band.

Fix: $2000 overhaul!
I now have metal pistons, a steel shuttle valve instead of aluminum, and an updated reaction hub with a long radius as well as other little goodies that hope-fully will make the tranny more bullet proof, and yes we built the tranny for VERY firm shifts (churp 2nd gear) because I also tow.

Closing: You could very well have a differant problem ie; selonoid, wireing , ect. bottom line is you should visit a tranny shop before any further damage Occures.
News for anybody reading this. You could have plastic pistons also, as it turns out chevy used both metal and plastic at randum you cannot differintiate between models and years, you have to remove the oil pan and accumalators for a visual inspection.

[jcarpentr2]

I realize I'm posting a reply late on this, but it might be information that is relevant to someone.

We have had the same problem with our 02 Z-71. The 1st-2nd transition can be very harsh especially under light load and easy acceleration. It actually seems better under harder acceleration and load. We took it to the dealer under warranty and they finally said there was a bulletin that suggests a wiring change at the alternator. Apparently, the alternator output was noisy and causing the tranny solenoids to switch states erratically. I call BS, but it "seems" that the change lessened the problem, but it still does have a harsher-than-normal 1-2 shift problem.

I finally said screw it and put on a Hypertech programmer and made all the shifts firmer. The 1-2 shift can still be harsh at times, but since I tow a lot now, the firm shifts are less of a problem than when fully UNloaded.