Will a Dana 36 from an 85 fit my 93 auto. its a 3:07 and will it make a difference. Thanks Jim

 

Yes I believe it will fit, however the 2 holes where the support mounts, from the trans to the rear, will have to be enlarged. Its not a big deal. What I did was remove the bolt and took it to the hardware store and purchased a drill bit in that size. The metal is soft, as a matter of fact I used a cordless drill to enlarge it. As far as if the 3.07 will help, I believe it will. Several people have switched them such as vettenuts and was happy with a 3.07.

 

I don't know about enlarging any holes. I did this swap last winter on my car and I didn't have to enlarge any holes. You need to use the torque arm for the Dana44 also. The one that is in your car is too long for the Dana44. The torque arm is that long c-beam that bolts to the output of the trans and the front of the rear diff. There will be many people argueing now about the drive shaft. I used the drive shaft that came out of the Dana44 car. It is slightly shorter than the driveshaft for the Dana36 cars. Some claim you can use the same driveshaft. Others claim you can't. Good luck. One other thing you might want to consider if you do the swap. When you have the diff. apart before you put it in the car drill a small hole from the inside of the case into the base of the bore of the bottom cover bolt. The hole is deeper than the length of the bolt so you will not be weakening the bolts ability to hold the cover on. When you put the bolt in use rtv silicone sealant on it. Now, when you want to change your rear diff fluid all you need to do is take out the bottom bolt and let the lube drain. Then use some more sealant on it and put it back in, then fill up through the fill hole. No need to suck it out or take the whole darn thing out of the car to change the fluid. I did this on mine and it works great. I learned this tip from somebody on the forum and I can't remember who, so thank you to whoever first posted this! I think this is a much better way than using that kit the parts catalogs sell that you have to drill and tap a large hole in the side of the case, and then hope the bolt makes a good seal. My way does not weaken the case at all.

 

Bob (Bob86ZZ4) please note, he is putting a D36 in place of a D36, not a D44 into a D36 car. The only difference I know of from early D36 to late D36 is the rear camber adjuster mounts use 2mm larger bolts on the later units. These are for the black brackets that the lower aluminum arms mount to.

Tom Melton
82 CE
86 Z51 Coupe


[Modified by tommelton, 3:04 PM 10/25/2001]

 

I'm confused I thought all autos had a Dana 36 am I wrong if so what does it have. Thanks Jim

 

Jim, yes all auto cars have D36s from the factory.

-Tom

 

These are the holes Im talking about enlarging.

 

Bob,

I don't quite understand the purpose of drilling the hole you described. Can't you drain the diff case from the 13mm (M-8) drain bolt as intended from the factory? Chilton's manual says you can.

Someone may have done the mod you sugessted to my 'vette. I tried to drain the diff by removing the drain bolt. When I removed the bolt, no fluid came out. I shined a light into the thread hole, and saw a bunch of silicone stuck inside. I tried to pick all the silicone out, because I thought this was preventing the lube from draining. The silicone was way up in the hole, and I couldn't get it out. I let it sit overnight and only a few drops of gear oil came out of the hole. I removed the filler plug, and the level was still full.

Finding that someone siliconed the hole kind of pissed me off, because how are you supposed to get all the silicone out if you do this mod? :nono:

 

I believe the silicone you see is from the assy of the unit. They dont use a gasket. On my orig. diff. and my replacement, the holes do not go all the way in. I remember someone posting that you could drill it through and one of the rebuilders posted not to do this, that it would void the core value of the unit. Most of us spifion the oil out of the diff. to change it. you can use something like the mity vac to do this.

 

Turismo: there is no factory drain hole on these diffs. I'm guessing you took the bottom cover bolt out hoping the fluid would drain out. That is the hole I was referring to above that you can drill into from inside the case when you have the diff taken apart. I know about people claiming that this eliminates the core value of the unit. So. I would feel more comfortable changing my fluid often and when/if the diff goes out having a good rebuilder just rebuild it, rather than swapping it for another one with an unknown past. I did change the fluid in mine once using the vacuum method, what a hassle. Much easier to take the bolt out and walk away for awhile.
Tom: sorry, I guess I didn't read his post close enough. I just assumed he wanted to go to a Dana44. Doesn't everybody? Shame on me.

 

my comment would have to do with the brakes....i believe the newer models have larger rear brakes and for sure the abs. so the center section should swap (except as noted on the hole sizing) just keep your present brake setup!

 

What!? No drain plug? What were these people thinking? :boxing