4+3 Transmission
Thread Starter
Intermediate
Joined: Mar 2002
Posts: 48
Likes: 0
From: Milwaukee Wisconsin
4+3 Transmission
I have an '87. Re: the transmission: Is it better to drive in the lower gears ( do not engage the OD) at a RPM at or lower than 3500, or while in slow city traffic?
thanks
thanks
Melting Slicks
Joined: Oct 2000
Posts: 3,426
Likes: 4
From: Heidelberg PA
Cruise-In V Veteran
Re: 4+3 Transmission (Shifty Wizzard)
The 4+3 is an interesting and good tranny if you do a few things.
1) Use OD on Highway only - Very expensive to repair and most tranny shops have never seen one. Ask me how I know!!!!!
2) Religiously change the fluid & filter every year. Most problems occur because maintenance did not occur.
I know others can chime in.
Enjoy,
1) Use OD on Highway only - Very expensive to repair and most tranny shops have never seen one. Ask me how I know!!!!!
2) Religiously change the fluid & filter every year. Most problems occur because maintenance did not occur.
I know others can chime in.
Enjoy,
Racer
Joined: Mar 2004
Posts: 311
Likes: 0
From: Oakley Ca
Re: 4+3 Transmission (85vet)
85vette is right. Overdrive is for hiway travel. Service often. Although it is not required I use the clutch when shifting in and out of overdrive. I don't know if it helps, but is a habit from 2 speed rear end driving. Mine went out around 30K miles and was told by an "expert" that was predictable. Not the best OD in my opinion. Service often. Cheap insurance.
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Re: 4+3 Transmission (olman)
I use overdrive as a 5th gear.
Also, sometimes when 4th gear is too low and 4thOD is too high, I'll use 3rdOD.
And... if I'm 'lurking' I'll drive in 2ndOD at 2500 rpm. A quick flip of the switch and I'm instantly in my powerband in 2nd gear and ready to rumble. Faster than you can clutch and faster than an automatic can react.
I've considered wiring an OD switch to the steering wheel for quick access when I need an instant downshift and don't have the time to clutch or reach for the console switch.... which happens often on the canyon roads here in Califoreignya.
:steering:
Also, sometimes when 4th gear is too low and 4thOD is too high, I'll use 3rdOD.
And... if I'm 'lurking' I'll drive in 2ndOD at 2500 rpm. A quick flip of the switch and I'm instantly in my powerband in 2nd gear and ready to rumble. Faster than you can clutch and faster than an automatic can react.
I've considered wiring an OD switch to the steering wheel for quick access when I need an instant downshift and don't have the time to clutch or reach for the console switch.... which happens often on the canyon roads here in Califoreignya.
:steering:
Safety Car
Joined: Mar 2000
Posts: 3,581
Likes: 1
From: Springfield VA
Re: 4+3 Transmission (Shifty Wizzard)
I use mine all of the time. However, I also use the clutch just like any other shift. I really enjoy driving some twisties where I use the OD to optimize gear selection. (think of a 3 low to a 2 high upshift) Use of clutch and proper maintenance will go a long way to providing a long life for your 4+3.
Drifting
Joined: May 2002
Posts: 1,509
Likes: 3
From: Hazel Park MI
Re: 4+3 Transmission (96LT1)
I think us 4+3 guys may not read our owner's manual, not shop manual, very closely. The owner's manual states to leave OD on all the time. For me, it depends on the driving. Always on the Eway, sometimes in the city. :seeya
Melting Slicks
Joined: Oct 2000
Posts: 3,426
Likes: 4
From: Heidelberg PA
Cruise-In V Veteran
Re: 4+3 Transmission (jmrl98)
The manual does not have to pay for repairs.
The mentioned tips are from experience, not a service manual.
If you believe and follow everything GM says, then by all meens leave it on all the time.
However, If you want consistant long life do not leave it on all the time!!!
The mentioned tips are from experience, not a service manual.
If you believe and follow everything GM says, then by all meens leave it on all the time.
However, If you want consistant long life do not leave it on all the time!!!
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Drifting
Joined: Dec 2003
Posts: 1,492
Likes: 94
From: Westfield MA
Re: (scorp508)
I try to use the OD like a 5th gear but sometimes I just leave it engaged and just wind it up a little extra in 1st so the shift to 2nd/OD isn't so extreme. I also clutch it when engaging or disengaging the OD. I have tried it both ways and the clunk doesnt feel right for me. Seems like it will take its toll over time.
Thread Starter
Intermediate
Joined: Mar 2002
Posts: 48
Likes: 0
From: Milwaukee Wisconsin
Re: 4+3 Transmission (jmrl98)
Thanks, but I'm going with the guys who use it on the highway, not in the city or slow driving. You have to do what's good for you. Right? However, I have had the car for the past 4 1/2 years and used it the same as you. Just haven't changed the fluids or folter yet.
Drifting
Joined: Mar 1999
Posts: 1,931
Likes: 1
From: Norcross GA
Re: (Shifty Wizzard)
That "clunk" that I get,... is a good thing. It tells me the unit is engaging firmly. This means it is a firm unit. No slipping.
I have tried many different way's to get a smooth shift, but the clunk alway's seems to get me. (I'd like the OD unit to shift faster as well.)
Bottom line,... I don't sweat it.
I have tried many different way's to get a smooth shift, but the clunk alway's seems to get me. (I'd like the OD unit to shift faster as well.)
Bottom line,... I don't sweat it.
Heel & Toe
Joined: Aug 2003
Posts: 15
Likes: 0
From: Independence MO
Re: 4+3 Transmission (nitrous1)
I too try to use the OD only on the highway. I will use 3rd OD from 50-60 mph and then kick it to 4th OD above that. I found using the OD below about 40-45 mph a bit of a hassle...I found myself switching it on and off more frequently than I probably should.
Heel & Toe
Joined: Aug 2003
Posts: 15
Likes: 0
From: Independence MO
Re: 4+3 Transmission (Shifty Wizzard)
Speaking of filter and fluid change on the overdrive.....
A friend of mine is a GM mechanic and he suggested to NEVER change the fluid in the overdrive. The more I read this and other posts on this topic, the less I believe this to be correct. Has anyone else heard this suggestion before?? It seems obvious that my father (the original owner of my Gold C4)
had it done at one point in its life.
A friend of mine is a GM mechanic and he suggested to NEVER change the fluid in the overdrive. The more I read this and other posts on this topic, the less I believe this to be correct. Has anyone else heard this suggestion before?? It seems obvious that my father (the original owner of my Gold C4)
had it done at one point in its life.
Drifting
Joined: May 1999
Posts: 1,478
Likes: 3
From: Sacramento, CA Money can't buy happiness - but it's more comfortable to cry in a Corvette than a Yugo.
Re: 4+3 Transmission (Golden85)
Gordon Killebrew who is THE MAN when it comes to C4s told me to use it as the manual specifies. He also said to change the OD fluid EVERY 12k miles or once a year whichever comes first.
I cfollow the above recommendation. So far, I've got 79k on mine at it still works great.
I cfollow the above recommendation. So far, I've got 79k on mine at it still works great.