Six Speed Blues

[Alric]

I have a 1996 LT4 car and had a little problem. The shifter does not have a reverse lock out, unlike the '89 I used to own, and I missed 6th and ground the reverse gear. It was not a hard or harsh grind, but it seems that it was enough to mess things up. It is very difficult to keep the car in reverse now. It is hard to shift into reverse, and then you have to hold the shifter down while backing up. The problem did not arise until I miss shifted the car; also the problem seems to be worse in cold weather. I am angry that I let this happen and hope to hear some suggestions as to what has happened the transmission and what I may be looking at for repairs.


Thanks,

Alric :confused :bash

 

[Vettelt193]

Mine is a bit hard to get in to reverse when it is cold, and it doesn't want to stay in sometimes... You may try changing the fluid first, before you go spend the big bucks... that is on my to do list, I hope it helps the problem.

 

[lt4 gs]

I have a 1996 LT4 car and had a little problem. The shifter does not have a reverse lock out, unlike the '89 I used to own, and I missed 6th and ground the reverse gear. It was not a hard or harsh grind, but it seems that it was enough to mess things up. It is very difficult to keep the car in reverse now. It is hard to shift into reverse, and then you have to hold the shifter down while backing up. The problem did not arise until I miss shifted the car; also the problem seems to be worse in cold weather. I am angry that I let this happen and hope to hear some suggestions as to what has happened the transmission and what I may be looking at for repairs.


Thanks,

Alric :confused :bash

I believe you blew the synchro for da backup gear........which will require a full rip it out of da car and replace da gear and da synchro.............sorry for the humor in my reply ......I was trying to ease the pain.......that you are going to feel..........start saving.....
I know how you feel..........because I have to go down this highway in the spring.......I missed second at the track .......one fine day and blew just the synchro....but the gear has to be replaced with the synchro. I haven't heard yet where the best places are to have these repaired........so this will be an interesting thread........also I am going to move it over to the c4 tech forum.....since we aren't the only zf's out there. Being a special heat treated process for the repairs there are very limited facilities that specialize in this type of surgery.........

 

[CKA_Racing]

Wow, sorry to hear you are having issues. I'm no ZF expert so i can't help you there. I have a ? for you though. I though the 95-96 cars did not have a reverse lockout? Is that false?
Also, what kind of shifter is installed? or did you buy with a non-stock shifter installed?

 

[secondchance]

CKA Racing.
He is right. At least 96 (maybe 95 as well) had factory shifter that did not have the reverse lock-out ring.

 

[Gorgon]

That's what he said originally. He has a 96 that does not have a reverse lockout, hence his current situation. He previously had an 89 that did have a lockout. 95 and 96 cars do not have a reverse lockout.

 

[mvftw]

Before I go into reverse I go into 2nd gear then reverse. It seems to help.

 

[ArtZR1991]

VetteLT had an excellent suggestion. I would really have the fluid flushed out and replaced. You can chose to live with the problem because of the expense of the repair, but if there is any debri in the oil, more problems are inevitable.

Be sure to change the oil. See if there is a procedure for "flushing". Anyone know of one?

Regards,

 

[Vettelt193]

I guess if you change the fluid, drive the car a couple hundred miles, then do it again it would flush out everything... that is the only thing I can think of that is relatively easy

 

[bogus]

The ZF Guru. The God of all things ZF:

www.zfdoc.com

 

[lt4 gs]

This is tricky......but one would surmise out of several thousand members that one or two members might actually know of places or people that are qualified to repair ZF6's..........the ZF Doc is a good link if you are in Arizona...........What about Michigan or Illinois for example?...........all the posts in this thread don't really seem to provide a solution ............just my two cents............

 

[NewGuy]

I have an LT4 and so does my friend. Always hard to get into reverse. If not perfectly in reverse, pops out. (really aggrivating that when you put the shifter back in reverse, it seems to only need a short push like 1/4'' or so). Everyone I talk to says it is a pain to get into reverse. Always thought this was part of the LT4 experience for everyone! By the way, moving into 2nd and then to reverse always helps.

Lastly...is there a syncro on a reverse gear?????? seems unnecessary.

Very Lastly...GM procedures for dealers to work on ZF tranny: Crate it and ship it back East. It is on a dealer bulletin.

 

[Alric]

Thanks

I drained and replaced the fluid with Mobil 1 motor oil. The transmission shifts better and the problem is less frequent, although still present. I talked with several people and read as much information a time would allow before using this oil. After driving the car for a few days now, I feel confident in my decision.

Thanks to all who replied,

Alric

 

[vintage]

I also have an LT4, six speed. Be aware that dealers cannot even work on the 6spd! They will pull your tranny and ship it to Sloatsburg, New York. That is the only shop in the country that can work on them. My car was out of commission for 4 weeks and cost including shipping exceeded $5,000. Transmission problems are major!

 

[lt4 gs]

Here' s a little less expensive solution.......direct from the General........at $3750.00 it's reasonable

GM PART # 12455189
CATEGORY: Transmission Assembly
PACK QTY: 1 CORE CHARGE: $3,000.00
GM LIST: $5,357.14
OUR PRICE: $3,750.00
DESCRIPTION: REMANUFACTURED 6 SPEED TRANSMSSION



http://gmpartsdirect.com/results.cfm

 

[vettl83]

Arlic, check out White Racing Products at www.whiteracingproducts.com they are located in Tampa Florida. They can rebuild yours or send you a remanufactured one. They have them on the shelf. They can also rebuild them to handle any amount of horse power you can mod your motor out to. A lot of the ZR-1 guys use their services. Nothing wrong with the ZF Doctors either. As we know nothing fixes itself. Good luck 84 CF 91 ZR-1