Tired 4+3 (Replacement Options)
Thread Starter
Instructor
Joined: Oct 2006
Posts: 246
Likes: 2
From: Elk Plain WA
St. Jude Donor '11
Tired 4+3 (Replacement Options)
In lieu of buying an after market 5 speed, is it possible/practical to replace the 4+3 with a Muncie and keep the DN Overdrive unit?
Racer
Joined: Sep 2004
Posts: 258
Likes: 0
From: Coram NY
Usually the problem with the 4+3 unit is the overdrive, if you are experiecing problems that might seem like bad syncros, like popping out of second gear, or problems in reverse it is the overdrive unit not the transmission. It does not matter if you are in overdrive or not for the symptoms to appear.
Tom
Tom
Thread Starter
Instructor
Joined: Oct 2006
Posts: 246
Likes: 2
From: Elk Plain WA
St. Jude Donor '11
Hummmm
Usually the problem with the 4+3 unit is the overdrive, if you are experiecing problems that might seem like bad syncros, like popping out of second gear, or problems in reverse it is the overdrive unit not the transmission. It does not matter if you are in overdrive or not for the symptoms to appear.
Tom
Tom
Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
I would believe that the trans could be causing this as well.
The answer would be to pull the side cover, and inspect the synchro teeth, and use a magnet, dredge the bottom of the case for metal particles. Synchro particles aren't magnetic, so you will have to use your fingers for finding them.
If you find steel, the trans (4 speed part) may need some attention by a competent rebuilder.
If your overdrive works just fine, it goes into overdrive, and whether or not the trans stays in gear, if the overdrive is still engaged, I would look for a bearing problem in the trans, and other maladies.
I was told by a guy that was onthe r&d team for the 4+3 that if your trans is hard to go into reverse, the overdrive is probably the culprit.
BUT!
find a close ratio cast iron saginaw 4 speed, and use the gears out of that. He said it makes a trans that has a lower 1st, and a higher 3rd gear. Essentially tuning for high speed, and hard launches.
The answer would be to pull the side cover, and inspect the synchro teeth, and use a magnet, dredge the bottom of the case for metal particles. Synchro particles aren't magnetic, so you will have to use your fingers for finding them.
If you find steel, the trans (4 speed part) may need some attention by a competent rebuilder.
If your overdrive works just fine, it goes into overdrive, and whether or not the trans stays in gear, if the overdrive is still engaged, I would look for a bearing problem in the trans, and other maladies.
I was told by a guy that was onthe r&d team for the 4+3 that if your trans is hard to go into reverse, the overdrive is probably the culprit.
BUT!
find a close ratio cast iron saginaw 4 speed, and use the gears out of that. He said it makes a trans that has a lower 1st, and a higher 3rd gear. Essentially tuning for high speed, and hard launches.
Last edited by coupeguy2001; Mar 15, 2009 at 03:08 PM.
Thread Starter
Instructor
Joined: Oct 2006
Posts: 246
Likes: 2
From: Elk Plain WA
St. Jude Donor '11
Need to Inspect
Some good suggestions offered.
I'll do some inspection as suggested and see if I find any damage. I think I will remove the short shift arms and put the original shifter arms back in it and adjust the linkage, test drive some before doing a swap or rebuild.
I assume the ZF6 is the tranny first offered in the 89?
Thanks for the help on this issue!
I'll do some inspection as suggested and see if I find any damage. I think I will remove the short shift arms and put the original shifter arms back in it and adjust the linkage, test drive some before doing a swap or rebuild.
I assume the ZF6 is the tranny first offered in the 89?
Thanks for the help on this issue!
Team Owner
Joined: Feb 2006
Posts: 24,460
Likes: 7
From: sw Ohio
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Drifting
Joined: Dec 2003
Posts: 1,493
Likes: 94
From: Westfield MA
Check this out:
http://members.cisdi.com/~anesthes/f-car-t5/
I think for an older C4, the T5 conversion is attractive, probably the cheapest option, if your engine is not modded, it should be adequate strengthwise, and it is a common easy to service transmission. I think some of the other conversions are "better" but are all more expensive and it doesn't pay to sink a lot of money into these cars.
http://members.cisdi.com/~anesthes/f-car-t5/
I think for an older C4, the T5 conversion is attractive, probably the cheapest option, if your engine is not modded, it should be adequate strengthwise, and it is a common easy to service transmission. I think some of the other conversions are "better" but are all more expensive and it doesn't pay to sink a lot of money into these cars.