Trans Turbo 400 with dana 300 case, mounting location for transfer case shifter

[Jck1980]

Hello everyone, I was wondering if anyone has any experience with installing a GM turbo 400 transmission with a dana 300 transfer case; into a CJ7. I would really love to get any advice of the location chosen for the sift handle for transfer case. In other words; where you cut the hole in the floor. Given how much further back the transfer case is in comparison to a manual tyranny. I currently have an AMC version turbo 400 with adapter from advanced adapters to my dana 300 case. This whole setup is currently all attached to a AMC 304, ( WICH HAPPENS TO HAVE A ROD HANGING OUT THE SIDE OF THE OIL PAN) LOL!
My goal is to utilize a GM LS 5.3 I own, paired to a Gm version turbo 400. Also using the same adapter I already have to connect the dana 300 to the turbo 400 gm version.
The only reason for going that route is due to the expense of rebuilding the AMC 304. I'm also not to crazy about the rotated mounting angle of the AMC version th400. That rotated angle in addition with the angle created from the adapter for the dana 300; causes issues with connecting the transfer case shift linkage. Any help with this would be greatly appreciated if anyone has ever built their CJ7 with these components. Thankyou so much! I'd rather have a manual, lol, but my wife is stuck on an automatic so she can drive it. She's interested in doing this build with me, so its something I'm willing to do for her experience with it. Thanks again, any help is greatly appreciated.

 

[TSB8C]

I have a GM 350 with a 700R4 auto (wanted the overdrive) and a Dana300 with a Novak adaptor. I twin-sticked the Dana300 using a Currie kit that has adjustable extensions that allows you to move the shifters forward to accommodate longer drivetrains. So my shifters are still in the stock location next to the tranny shifter. I also purchased a blank tunnel cover so I could cut my own openings for the Lokar tranny shifter and the twin stick shifters. Here's a link to the shifter kits to give you an idea about the adjustable one. Looks easy enough to make an adjustable bar/shaft if you aren't changing the shifter or adding twin sticks. Omix also makes an adjustable twin stick kit as well.

Novak Twin Stick Kits
Omix Twin Stick Kit

 

[Jck1980]

Awesome! Thankyou for that bit of intel. I almost asked about longer shift rods in my original post. Lol, im a 20 plus year body man and decent mechanic; The 4x4 stuff is pretty new to me though. I'll definitely check that out soon. So does your dana 300 hang at a downward angle? Curious to hear the difference from Novak adapter and my advanced adapter. My dana 300 sits at a pretty mean downward angle. Partly due to the way the amc th 400 mounts to the engine. Thankyou again!

 

[TSB8C]

My Dana300 is straight inline with the Novak adaptor connecting it to my tranny. Now I do have a 4" suspension lift which included spacers to drop the skid plate down slightly, plus my rear springs slightly rotate the diff upward via the spring perches as well. So my rear drive shaft, even with the longer driveline, is still OK with no wild steep u-joint angles. Without the lift springs and drop spacers for the skid plate, the longer driveline would certainly have put stress on my rear shaft. And of course I also had to get custom drive shafts made to get a longer front one and shorter rear one.

 

[Jck1980]

Thanks for the info! Yes I see that my skid plate has been lowered as well, not factory skid plate. I'm on a roll now with the longer shift linkage for the dana 300. Lol

 

[Wild Heart Jeeper]

My Dana300 is straight inline with the Novak adaptor connecting it to my tranny. Now I do have a 4" suspension lift which included spacers to drop the skid plate down slightly, plus my rear springs slightly rotate the diff upward via the spring perches as well. So my rear drive shaft, even with the longer driveline, is still OK with no wild steep u-joint angles. Without the lift springs and drop spacers for the skid plate, the longer driveline would certainly have put stress on my rear shaft. And of course I also had to get custom drive shafts made to get a longer front one and shorter rear one.

TSB8C I am building almost the same setup as yours, though with a less powerful SBC crate engine. That seems right on target with the Novak twin shift kit. One of the reasons I purchased it was for the adjustable linkage. But I am not quite to the step of mounting it yet because I am stuck on trying to establish sufficient clearance between the front drive shaft and the 700R4. Just curious how you arranged that? And how much clearance you ended up with?

 

[TSB8C]

TSB8C I am building almost the same setup as yours, though with a less powerful SBC crate engine. That seems right on target with the Novak twin shift kit. One of the reasons I purchased it was for the adjustable linkage. But I am not quite to the step of mounting it yet because I am stuck on trying to establish sufficient clearance between the front drive shaft and the 700R4. Just curious how you arranged that? And how much clearance you ended up with?

The 4" suspension lift helped that issue. I also have a smaller diameter thick wall front drive shaft. No clearance issues at all. I also recall swapping the drive shaft so the slip joint is at the lower end.

 

[Wild Heart Jeeper]

The 4" suspension lift helped that issue. I also have a smaller diameter thick wall front drive shaft. No clearance issues at all. I also recall swapping the drive shaft so the slip joint is at the lower end.
View attachment 85135

Thank you for the post! That sparks a couple of questions. Do you have the wide track Dana 30 front axle? And to what degree is your transfer case clocked? Would you mind posting a picture of the driveshaft where it passes by the transmission, looking along the shaft toward the transfer case?

 

[TSB8C]

Here's a few pics of my front shaft near the transmission pan and coming from the xfer case. My xfer case is not clocked at all. Stock except the twin stick kit. My axle is a wide track Dana 30.



Perhaps what doesn't show too well from these angles is that the shaft is actually to the side of the trans pan, not directly under it. So the shaft can move up/down to the side of the pan since I have a smaller diameter shaft. The original stock shaft wouldn't have cleared. Also keep in mind that I do not require longer travel of the front suspension since I do not do any rock crawling or other hard core wheeling. This is a street driver and minor camping and deer hunting rig. My skid plate is also dropped using the spacers supplied in my 4" lift kit to change the rear drive line angle.

 

[Wild Heart Jeeper]

Thanks for the additional pictures! That really clears it up. What kind of adapter did you use between 700r4 and xfr case"?

 

[TSB8C]

I used the one from Novak (Part # 137A). I also got their twin stick kit (part # TX300), their twin stick knobs (part # KBLTBK716), and their dual shifter boot (part # TSB). I used their blank tunnel cover so I could cut my own holes for the shifters (part # F-7TTC) and their rear trans mount (part # RMU). Just had to drill new mounting holes in the skid plate once I had the engine/tranny/xfer case all in place and lined up where the mount needed to be. My trans shifter is a Lokar (Part # CM700AM). I used the Omix-Ada 18606.03 boot for this Lokar shifter. That is a boot for a transfer case, but worked perfect on the Lokar tranny shifter.

 

[Wild Heart Jeeper]

I am using all the exact same parts, with exception that the adapter came already installed on the transmission from Novak. It was a little hard to see it in the background of your pictures, but it appears you have the xfr case “clocked” in the second position down from straight level. I have tried that also, and it seems to be the best clearance the driveshaft can achieve, and mine looks more or less the same as yours when I put it in that position. Unfortunately, I am still concerned that it might have a damaging collision between them when off-road obstacles get a little hairy. And I do do some off-roading, though not too much rock crawling as I am NW Florida. We have to import rocks if we need them around here

Seriously though, I have two concerns with the xfr case being in that position. First, will it lubricate properly? And second, because I also replaced the factory bottom pan on the D300 with the D328-D billet aluminum deep bottom pan from Novak, clocking it that far down also causes me to have to shim the transmission rear mount up by about 1 1/4in to clear the pan from the skid plate. also makes it almost impossible to remove and replace the xfr case drain plug without major disassembly.

 

[Wild Heart Jeeper]

 

[Wild Heart Jeeper]

Any further thoughts after seeing the pictures would be appreciated.

 

[TSB8C]

I don't recall clocking mine, but maybe I did as you have indicated. My angle seems similar to yours in the pics. I also can't remove the xfer case drain plug without dropping the skid plate due to the further back position due to the tranny/adapter combined length. I retained the stock xfer case pan, so no issue with shimming it for additional clearance. I've never had any known issue with lubrication in the xfer case after about 4 years now. In terms of front drive shaft clearance, it is close, but no issue for me with any contact with the tranny pan using the narrower diameter drive shaft. One thought: is your engine centered or off a bit to the passenger side. Some people when doing a SBC swap move the engine slightly off centered to allow clearance of the steering shaft with the SBC exhaust. If the engine is moved to the passenger side any, that would put the front drive shaft closer to the tranny pan since the front diff is on the passenger side. If you have the clearance, you could move the engine back to the driver side slightly to pick up another 1/2" or so.

 

[Wild Heart Jeeper]

My engine is off centered to the driver side 1 1/2in and the transmission is off center to driver side an equal amount, measured at the rear output of the xfr case. Shifting it over was relatively easy with the Novak small block Chevy motor mounts and this seems to give the most front driveshaft clearance I can squeeze from it. I am already sweating a bit over the steering shaft to headers clearance, but think I have that part worked out.

It is starting to look like the only way to get any more driveshaft clearance would be with a two piece front shaft. So I will work on the geometry and see if that looks feasible. I will update the thread when I get it worked out. Thanks for all your help!