HELP Rear wheels Locked up while driving

[Dogpoor]

Help,
My wife was driving our 2003 H2 with 50K yesterday and manually downshifted the Hummer from 3rd to 2nd while approaching a downgrade. She wasn't driving faster than 20 mph. The rear wheels locked up momentarily and the engine shut down. Sounds like something I have down accidentally shifting from drive to reverse in an old Suburban. I tried to recreate the situation but cannot. Any input would be great. Thanks

[2010_5thgen]

why did she downshift the gears in the first place? its cheaper to replace brake pads than it is transmissions.

[H2005]

Hopefully they don't have to find out the hard way.

[Olfart]

I live in the mountains of North Georgia and I have been downshifting to 3rd and 2nd regularly for over 5 years to get engine braking. Have never had a problem. Looks like something in the rear end decided to lock up....most like ly a random failure not associated with downshifting the tranny

[HummerJim]

Sure she didn't accidentally push the shifter slightly forward into Reverse? I did that one time on a downhill trail in the heat of the moment on one of the Lynch Hummer dealer sponsored outings doing what I thought was downshifting (there was also the distraction of a wasp in the cab) and it locked everything and shut down the engine. I could have sworn I didn't push forward into reverse, but the wife was next to me and said otherwise. We also were going very slow, perhaps 10 - 15 mph.

[StockStar]

Originally Posted by 2010_5thgen

why did she downshift the gears in the first place? its cheaper to replace brake pads than it is transmissions.

[Dogpoor]

Thanks for the input. Yep brakes are cheaper than trannies. We lived out west in the mountains and got used to engine braking. I tried to recreate the situation but could not. I think that she inadvertantly shifted to reverse (I hope so). Thanks again and I'll update if something new happens.

[VegasGuy]

I have used engine braking in all my vehicles including my H2 and never had an issue. Just a wild guess, but I think my wife would be reluctant to 'fess up if she accidentally shoved the tranny into reverse, "I'm not stupid! I would never do that!"

[[__--MUD--__]]

Keep your finger off the button and it wont go in reverse