Last night when I pulled my IROC in the garage (after a relatively fast drive home on the highway :-) ) I pulled the car in a little too far. So, I put the car in reverse, took my foot off the brake and it didn't move. I thought this was strange because it usually moves easily in the garage at idle speed in reverse or drive. So, I gave it a little gas and it moved in reverse, but only a little and once I let off the gas it stopped. It seemed like I was stuck on something or something got caught under a wheel. So, I put the car in park and got out and checked. I didn't see anything. So, put it in reverse again and it did the same thing. Another strange thing was when I put the car in neutral and the car moved forward!

I changed from reverse, neutral and drive a few times and still no difference. I also noticed that the car didn't "twist" like it usually did when I went from reverse to neutral and neutral to drive. So, I put the car in reverse and gave enough gas (which ended up being quite a lot!) to get it out of the garage and into the driveway. I think I heard some strange noise as the car crawled out of the garage. But, it was kind of tough to hear it over the Borla. Once I got into the driveway, I tried going from reverse, neutral and drive again and it did the same thing it did in the garage. I put the car into neutral and it actually creeped UP the driveway!

So, I made a few quick trips up and down the driveway and the problem went away. I don't know what it was. It seemed like it wasn't going totally into reverse and neutral was sort of like forward.

Is there some linkage that is/was screwed up? Or is my tranny really close to be toasted? I have been suspicious of this transmission because of some other issues, so I wouldn't be surprised if it is finally going.

I didn't drive it to work today because if it is just some broken or loose linkage, I would think driving it 12 miles to work would really cause problems.

Any help would be greatly appreciated.

Thanks!

Paul
'89 IROC-Z AT

 

Try adjusting the linkage. If that doesn't work, its toast.

 

Mine did that at one point along with making a grinding noise while at 45 mph. If I had taken it in to be looked at then ...sigh....probably would not have cost me a 1195 dollars later.

BAAADDDDD CHRISTINE!!!!!!!!

 

What you describe sounds like what happens when the Forward Clutches are welded together but that won't "fix" itself as yours seems to have done. How does it act otherwise? What if you get on it hard in Forward, does it slip at all? What is the fluid level and condition? Being that we are almost neighbors perhaps you want to bring it by for a look/see?

 

Sorry. Double posted somehow.

 

I'm having this exact problem, but it's on a freshly overhauled unit. I wasn't about to drive it to see if it would "break loose", so I pulled it back out, and now have the valve body off, and input drum apart. I don't see anything whatsoever that could be causing this! It's definately the forward clutches not releasing. The only difference I'm having is that it only happens after being put into a forward gear. I've rebuilt several of these, and many more 4L60-E's and never had this problem!

Just for reference, the original failure was the 3-4 clutches, due to the seal betweee the input and output shafts failing. I also did NOT take anything apart in the valve body, just check all the passages I could see, and moved all the valves to make sure none were stuck.

I'm gonna grab my book and go look it over and re-assemble it and scrutinize everything!

Thanks in advance!

 

JP84Z430HP,

Sorry to hear that you are having this problem. Mine never did it again so I never found out why it did it. However, I thinkg my tranny finally did go in October of 2002 (just before putting it away for the winter!) It won't shift out of 1st gear. Also, reverse still works. I haven't gotten it fixed yet. In fact it stayed in storage all last year.

I have been investigating what to do about it. I may get it rebuilt by a local guy or spend the extra $$$ and buy a GM remanufactured one.

Good luck with yours!

Paul

 

Man, I'm sorry to hear about your troubles! I would reccomend a Pro-Built transmission over a reman anyday..... He does stuff that makes a 700 work much better than even GM intended! I've talked to Dana a few times, and he really knows what's happening inside a 700!

As for the trouble with the one I was working on (It was actually in an Astro van, for a friend) I found that I had gotten the valve body gaskets mixed up. They send 2 in most paper/rubber kits, and I had one of them wrong. I think it was the one on the VB side.

After fixing that and putting it back in, I could not get it to shift into 4th gear running it in the shop with the rear wheels off the ground. It also did it on the first trip down the road. After I turned around and headed the other way down the road, it was perfect. Just as GM built it anyway. I can't be perfect without changing stuff, and this is just an Astro van, after all....

Hopefully, if someone has this problem in the future, they will find this in a search and learn from my dumb mistake!!!!

 

Maybe your parking brake is on or the cable is stuck on something?

Probably a dumb suggestion but thats what happens when you have it on