Engine/Transmission (1994 - 1998) Mission: G56 (pictures)

[Vaughn MacKenzie]

Nice install, any driveline vibes at highway speeds?



Having your name on the driveshaft is a nice touch :-laf

 

[GAmes]

Just not sure if it would screw up the ABS controller or anything.

It is just taking a signal from the controller so it shouldn't bother anything there. My controller is unplugged but Eric's is working. You would have to cut the feed wire to the speedo however so that it (the speedo) wouldn't be receiving two signals.



On edit; I used a friend's Tom Tom to calibrate the speedo. I dialed it in at about 30 then again at 45, then at 60. When I slowed back to 30 it read about 2 mph faster than my real speed. After messing with it awhile I determined that with it accurate at 60 it was accurate at all speeds (up to 80, on a 70 mph highway:-laf) down to 45 or so, then it just read a little fast. I'm guessing that the signal at lower speeds just isn't in tune with the little motor that drives the needle, sine waves and all that stuff I know very little about. The nice thing is if I'm showing 30 mph I won't get a speeding ticket. I once got one for 32 in a 30 on Ft. Hood in a 67 Chev PU that had a different transmission, rear differential and smaller tires than stock. I was amazed the speedo was as accurate as it was!

 

[GAmes]

Nice install, any driveline vibes at highway speeds?



Having your name on the driveshaft is a nice touch :-laf

I've only had it up to 80, no vibration, but I didn't expect any. I had a driveline shop in Austin that is famous in central TX lengthen and balance it along with the flange installation. There were about 200k on the u-joints and 400k on the center bearing so those were replaced.



They put my name on it and by coincidence the writing was in the picture, but what the heck:-laf

 

[GAmes]

One more thing before this thread is buried. I have a perfectly good cross member that anyone who wants to do this conversion can have for the cost of shipping.

 

[hsmith]

Gary, did you use Scotty's on Airport Blvd? I have several times with great results.

 

[Shadrach]

How would the 4x4 differ, if you know. Would the transfer case bolt up to the back of the G56 after the removing the flange?



The transfer case will bolt right up. We put a G56 in my buddies 93 W350 and I am putting one in my 03 4X4 . The bolt pattern and the splines are the same. The 93 uses a splined coupler to join the two male shafts. The newer units have a male shaft and a female shaft , no coupler. Shadrach

 

[GAmes]

Inland Truck Parts & Service on Anderson Lane. They used to be called Austin Drivetrain and have sterling reputation among the hot rodders up here.

 

[Rogan]

excelente! I am the jealous.

 

[HBarlow]

Gary, very nice work, good explanation, and good photos to show your work.

It is also an excellent foundation for a quarterly TDR magazine article. There is probably a lot of interest in the project, particularly among 12 valve owners.

You should write an introductory paragraph with a brief story of your truck, the odometer miles, what it is used for, and a line describing all the NV-4500 five speeds you've worn out. Maybe add an additional photo of the truck.

Send it to Robert Patton. I'm willing to bet he would like to publish it in a future TDR magazine.

 

[hsmith]

OK, I'll keep them in mind for the next need of mods. Closer for me also. Thanks Gary.

 

[Matt42]

Has anybody done this with a 4X4?

 

[ewcmr2]

Has anybody done this with a 4X4?

Not that I know of. The G56 doesn't have a traditional 2wd tailhousing, it has a flange to bolt a transfer case to it (or a U-joint adapter in a 2wd truck) so 4wd should be no problem. Just an extra driveshaft and 4wd shifter to make it fit/work.

 

[CanfieldOO7]

How much did this whole setup cost?

 

[GAmes]

How much did this whole setup cost?

Depends on what you want, how much you can do yourself and what you can find. I spent a day and the fuel to drive to Dallas to get my $2200 used transmission. It came with the stock DMF, clutch and PP but I discarded them and bought a Southbend kit for around $1000. There are clutch kits for less money at NAPA. I did the cutting and prep of the crossmember and paid a welder $40 to cut the steel and weld it in. When I had the driveshaft work done the u-joints had about 200k on them and the support bearing had 400k so I had them all replaced at the same time, $610 and two trips to Austin. The trans had no shift lever or boot, $120. Stock clutch linkage will work, mine had more than 300k of use, $310. I used the Fast Coolers from my NV4500, but they needed adapters from Genos, $20. The coolers require 2 more qts of ATF+4, 8 qts-$50. A local transmission shop wanted $450 to do the swap. I rented a transmission jack for $30 and a friend of mine and his very large 20 year old son helped me do it in my garage. I gave his son $200. The 5 speed had about 60k since it's rebuild, the SB clutch had about 160k. Sold trans, bellhousing, clutch, PP, flywheel and assorted parts for $1500.

That should give you some numbers to work with.