pezter22

I have an '84 with the Doug Nash 4+3 transmission and it's starting to give me a loud wining (bearing) sound. The car has a little over 80,000 miles and previous owners really did not maintain the car.

I'm in the Detroit area and my mechanic says i need to take care of it soon. I'm somewhat torn between rebuilding or going with a TKO 500.

My problem is it's hard to find anyone to rebuild the DN 4+3 and actually since Keisler went into bankruptcy it's getting harder to find a Tremec kit for the C4.

I'm really not a fan of the DN 4+3, (I also have a '91 with the ZF6 speed), So I am wondering what others think of the Tremec swap. I don't race, I'm simply a cruiser. The car has a Dana36 with 3:07 gears.

Any suggestions? Thanks in advance.

vetteoz

A ZF6 swap ?

http://members.cisdi.com/~anesthes/zf6/

hcbph

I can speak a little to a Tremec 5 speed swap as my 86 has one. I bought the car last summer and it already had the swap done when purchased, unfortunately I got no history on the car so this is what I know.
The car when built had a 4+3 with 3.07 rear end and L98 engine. It now has a Tremec TR 3550 transmission in it confirmed by Tremec. Tremec said the build date on the tranny was 2008 so it's around 6 years old. The car was on a lift having the clutch slave and master cylinder replaced after I got it home so I had a chance to look it over. The clutch master and slave are oem parts, the bell housing looks to be oem as does the swing arm and driveshaft from what I can tell. The shifter fits in the original location. There is a Dakota Digital adapter wired into the speedometer to do the signal conversion. The overdrive light will flick on and off on occasion on the Dic, not a big deal as I'm assuming that's a leftover from the 4+3 days.
This is a cruiser and while driving the car back from New Mexico (where purchased) to Minnesota I got a best of 32 mpg at 75 MPH on the highway - about 1800 rpms. It drives well around town but I've only driven a couple of hundred miles since getting it home. The only thing I'm not the most crazy about is it seems to rev the engine a little more in first before you have the speed to shift to 2d gear. The other thing is it seems a little awkward shifting into 5th gear, takes a little extra pressure to the right before getting into gear.
Maybe if I was racing or doing road courses this might be a big deal but this is a cruiser and nothing is that big a deal in that situation. I do like it and for the someone doing the driving style I do, I'd recommend it.

5-Speeds

The carrier bearing has gone bad in the OD. It should quiet down when in OD since the carrier is held stationary in that mode. Keep driving it like this and it will self destruct and you'll get stuck on the road.

Brian from SK does a great job rebuilding both the 4 speed and OD unit. Contact him at 631-957-9427.