Help! New C4 owner needs transmission experts
Thread Starter
Team Owner
Joined: Nov 2002
Posts: 138,701
Likes: 177
From: Poor pathetic little excuse for a boy
Help! New C4 owner needs transmission experts
Well, I just bought a '94 Automatic with 108k, and I was driving it the other day around 40 mph and it started going from 4th to 3rd to 4th to 3rd; maybe around 6 up/downshifts in 30 seconds. It was in overdrive of course. I put it in D after that, all was ok. Then back to overdrive and it seemed like it went away. No idiot lights on dash. Tranny fluid ok (level good and clean). Shifts fine; strong acceleration. What is up? Thank you in advance!
Team Owner
Joined: Sep 2001
Posts: 62,160
Likes: 1,733
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Probably due to the fact that ~40mph is the magic number, EPA guidelines force the computer to want to shift to 4th at around those speeds. So in effect the transmission is 'hunting' between the 2 gears if you are close to that speed. Once you stay over that speed for an extended time it will stay in 4th, but if your speed is fluctuating the transmission will shift.
This is why I leave my own car in D unless I know i'm going to be over 45mph for a few minutes at least. The 3-4 clutch pack will wear out.
This is why I leave my own car in D unless I know i'm going to be over 45mph for a few minutes at least. The 3-4 clutch pack will wear out.
Racer
Joined: Nov 2005
Posts: 456
Likes: 3
From: Sumner Texas
Although I am ASE certified on automatic transmissions, I don't consider myself an expert.
I will say, however, that the first thing I would do is make sure that there is a strong vacuum signal to the modulator. If there is not, check the modulator for leaks. If it is okay, check general engine vacuum. If it is low, find the leak and fix it.
Good luck,
I will say, however, that the first thing I would do is make sure that there is a strong vacuum signal to the modulator. If there is not, check the modulator for leaks. If it is okay, check general engine vacuum. If it is low, find the leak and fix it.
Good luck,
Burning Brakes
Joined: Aug 2002
Posts: 926
Likes: 2
From: chandler az
Just so you are aware the 94 has an electronic controlled transmission - there is no vacuum involved. 4l60e. Even the 4l60 which is the earlier no-electronic version did not use vacuum. It used a TV cable which controls line pressure in the transmission.
Le Mans Master
Joined: Oct 2004
Posts: 7,706
Likes: 485
From: Everett WA
C4 of Year Finalist (appearance mods) 2019
Originally Posted by vader86
This is why I leave my own car in D unless I know i'm going to be over 45mph for a few minutes at least. The 3-4 clutch pack will wear out.
jk.
Melting Slicks
Joined: Jan 2002
Posts: 2,238
Likes: 4
From: Milan
Originally Posted by vader86
Probably due to the fact that ~40mph is the magic number, EPA guidelines force the computer to want to shift to 4th at around those speeds. So in effect the transmission is 'hunting' between the 2 gears if you are close to that speed. Once you stay over that speed for an extended time it will stay in 4th, but if your speed is fluctuating the transmission will shift.
This is why I leave my own car in D unless I know i'm going to be over 45mph for a few minutes at least. The 3-4 clutch pack will wear out.
This is why I leave my own car in D unless I know i'm going to be over 45mph for a few minutes at least. The 3-4 clutch pack will wear out.
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Thread Starter
Team Owner
Joined: Nov 2002
Posts: 138,701
Likes: 177
From: Poor pathetic little excuse for a boy
Thanks for all the info! I am really enjoying my C4 experience so far. I am 6'5", so it is a little tight. But, it's tolerable since it is not a daily driver ('03 Lightning). The C4 experience is a much more organic experience than when I had my C5's. The "roughness" and edge of the car I believe add to the experience of driving it!
Thread Starter
Team Owner
Joined: Nov 2002
Posts: 138,701
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From: Poor pathetic little excuse for a boy
Latest word from SVT is NO gen 3...The concept Ford has shown is the four door Adrenaline, with like 390 hp (come on, gotta have at least 500!). Whoops, we better watch out, this may go to off topic!! :o