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1986 K30 6.2 Diesel Truggy Build - "The Mule"

Today I had a very insightful chat with Stephen at Off Road Design. We talked for a while about the build and options for the front suspension. I cannot say enough about how helpful and knowledgeable he is on these trucks.

After about a 30 minute chat I settled on a set of ORDs custom Alcan leaf springs. They will be about 5 inches of lift with the axle pushed 2 inches forward. The springs will go in the stock location and will be about 48 inches long. I was concerned with the weight of the diesel but Stephen assured me that was not a problem. I also bought their Front Upper Shackle Hangar (FUSH) and new bushings and shackles for the front.

Stephens estimates about 10-11 inches of wheel travel out of these springs. Hopefully I will not have to limit up travel too much with those huge 42s.

Now the worst part is the month long wait for the springs to arrive second only to what my wife will say when she gets the credit card bill this month.
 
Deuling Thanks for the info on the springs. Seems a shame to tear a new spring pack apart but that is the correct way to do it.

Since I got the front springs on order I have been more motivated to work on the truck. So last night I pulled the 205 out. I was amazed how easily everything came out. Took me about 2.5 hours to pull it including the driveshaft and crossmember.

I will say this that 205 is not light.

I wanted to confrim that my trans was the correct one to bolt onto the 4 speed Atlas that I have. And low and behold it is the correct trans and the Atlas will bolt right up.

Tonight's plan is to change the fluid in the Atlas and at least get the adapter bolted to the trans.

I am still not sure if I am going to have to trim out the floor some to clear the Atlas it will be tight. The Atlas is rotated up almost flat and the previous owner of the Atlas had it in a blazer with a 1 inch body lift and it was really tight. I guess we will see. . .
 
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Deuling Thanks for the info on the springs. Seems a shame to tear a new spring pack apart but that is the correct way to do it.

Since I got the front springs on order I have been more motivated to work on the truck. So last night I pulled the 205 out. I was amazed how easily everything came out. Took me about 2.5 hours to pull it including the driveshaft and crossmember.

I will say this that 205 is not light.

I wanted to confrim that my trans was the correct one to bolt onto the 4 speed Atlas that I have. And low and behold it is the correct trans and the Atlas will bolt right up.

Tonight's plan is to change the fluid in the Atlas and at least get the adapter bolted to the trans.

I am still not sure if I am going to have to trim out the floor some to clear the Atlas it will be tight. The Atlas is rotated up almost flat and the previous owner of the Atlas had it in a blazer with a 1 inch body lift and it was really tight. I guess we will see. . .

That 205 sure would look good behind one of my many 203's:whistle:
 
Just a quick update I did a trial fit with the atlas. It fits just need to massage the cab floor a bit to get a little more clearance on the rear of the case. I took lots of pics I will post them tomorrow.
 
Looking good :waytogo:

Get ready for some trimming on the front :D I keep finding more stuff these 42's like to rub on :doah:
 
Looking good :waytogo:

Get ready for some trimming on the front :D I keep finding more stuff these 42's like to rub on :doah:

I was afraid of that :doah:I am worried about my exo it is pretty far forward as you can see in the pic that tubing is like 6 inches forward of the rear of the front fender when measured at the bottom of the door. We left the rocker tube long so it could be trimmed to match the fender trimming.




Josh can you measure your truck at the same spot and see how far your fenders are trimmed? That tube is about at the firewall so I may be ok.
 
I will be at the shop later today so I can get some measurements for you. I'm now at 2" forward and my clearance problems are more toward the front (where the inner wheel well goes flat then bolts to the core support) the back side of the fender is good.
 
4 Speed Atlas Install Part 1

As I said earlier I picked the Atlas up used from a blazer that I parted. This is a Gen 1 4 speed Atlas. Shortly after this one was built Atlas stopped making all 4 speeds and redesigned it because they had oiling issues and bearings were failing in the reduction box. I spoke with advance adapters and they said for my application I should fine because the bearing failures were mostly in high speed race applications. They did however tell me if I broke anything I was screwed because not many parts were available for the gen 1 Atlas.

First thing was to get the old 205 out.





Check. Took me about 2.5 hours by myself. Everything came apart great. Before Installing the Atlas I wanted to change the fluid. It has two drain plugs one for the reduction box and one for the main case (the blue plugs in the pic)



When I pulled the drain plugs the oil looked pretty clean but both drain plugs had a lot of metal on them (they are magnetic)



Plug after I cleaned it off



Filling the case is a real PITA. You have to fill it through the sight tube. They recommend Amsoil GL-4. A 4 speed takes 2.5 quarts and it prob took 45 mins to get the 2.5 quarts into the case you have to fill really slow. You also have to tip the case onto the input to get the correct amount of oil into the reduction housing.



The previous owner did not purchase the advance adapters turbo 400 adapter for the Atlas instead he opted to go a different route. He ordered the Atlas with the round cough Jeep cough pattern on the front. Then he took a stock GM Turbo 400 to NP 208 or 241 adapter and slightly drilled out one of the holes to fit.

Front of Atlas. Note the multiple clocking positions. I left it where he had it clocked which was a few degrees from flat.



Trans side of adapter.





Atlas side of the adapter. Note the oblong hole in the lower left. It seems to fit great otherwise.





Rear of Atlas



Now lets talk about the trans. I was lucky and the Mule already had the right trans. It needs to be a short output 400 (the output shaft sticks out like 2.5 inches). My 86 was correct because it had the long input 205.



Trans with 208 adapter bolted to it.



Advance adapters makes it very clear that the output shaft of the trans must be less than flush of the adapter. You can see from the pic I had about a quarter inch of clearance which is perfect.



More tonight once I get it fully installed (hopefully)
 
Atlas Install part 2

So last night I got the Atlas slid into place and found out it did fit under the floor but it was really tight.





So this afternoon I took the atlas back out and clearanced the floor by tapping it up. See the two slightly pushed up areas in pic.



I gave it a fresh coat of undercoating and then put RTV on the Atlas and bolted it into its new home. Since I am using a factory 208 adapter for now I just used the factory 205 cross member and mount. I will build a better one later. The 205 cross member hangs really low it is the W style one.







Luckily I even had the square tube driveshaft out of the truck the Atlas came out of since I parted it out. I had to change the tiny 1310 yoke on the 60 to the huge 1410 yoke. It came off the 60 that was in the front of the parts blazer. That yoke was tight I was barely able to get it off.



The square tube shaft has a 1410 on the 60 end and it has a Dana 60 shaft U joint (1480) welded to a flange on the T case end.



Did a quick test and it all worked in high and low and low low. Next was to mount the cable shifters. I ended up cutting the floor about 3 inches wider where the 205 shifter cutout was. Then I made an aluminum plate to mount the shifters and screwed it over the hole in the floor. The twin stick shifters are actually reverse of a standard Atlas the way I mounted them. They are now High to the front of the truck and low to the back which works out well because the range box shifter is that way too. Now I want to buy matching billet knobs for the twin stick from Advance Adapters so they will all match.







The cable shifters are really a PITA to get installed and adjusted. But they seem to work pretty well. The High Low range box shifter cable is very tight to the Atlas case and rubs. I may have to shim that shifter at bit to get more clearance.

I did not have too much time to play with it but let me tell you that I had it in the 5.44 to 1 low low and when the diesel idled up because it was cold I could barely hold it back with the brakes. Just putting it in gear allowed it to idle up my driveway and I could have gotten out an walked next to it. I am having some trouble shifting from high to low in the Atlas main case but I think that it is because there is no rear driveshaft so the rear spins fast and the front will not go in. However if you turn the truck off it goes right in so I guess we will see once I get a rear driveshaft.

I cant wait to try it out for real on the trail.
 
Great writeup! The shifter plate turned out really nice. Are going to just remove the carpet and insulation now? I've heard stories of 4:1 doublers powering through brakes like that, i can only imagine what its like with that LOOOOW 5.44:1
 
Great writeup! The shifter plate turned out really nice. Are going to just remove the carpet and insulation now? I've heard stories of 4:1 doublers powering through brakes like that, i can only imagine what its like with that LOOOOW 5.44:1

Yeah the carpet has got to go. I want to bedliner the floor but I may look at some of that lizard skin stuff to help reduce noise and heat.

Yeah it easily powered through the brakes but I remembered this morning that the rear brakes are not hooked up yet so hopefully that will not be a problem once they are hooked up.

I think that the rear brakes may be what I tackle next. I have all the stuff for a disk conversion I just need to get one more piece of flex line and buy some hardline.
 
Dan, heres some front end pics

20130609_095446_zpsfb7a4116.jpg


20130609_095459_zps2bba9994.jpg




I think you maybe ok with your sliders, the problem im finding is with the inner up front when turning, im currently limiting to about 3" up and its still rubbing so trimming will happen this week.

If you think about it, pull tape from the bottom of your frame rail to the top of the axle tube and we can see exactly how much lift I have, 5" is really just a guess based on my rear setup.
 
If you think about it, pull tape from the bottom of your frame rail to the top of the axle tube and we can see exactly how much lift I have, 5" is really just a guess based on my rear setup.

Josh, I pulled a tape from the bottom of the frame rail to the top of the axle tube. Looks to be about 8.25 inches with the negative arch factory springs. Keep in mind that I also have a heavy old school Ramsey winch and winch bumper in addition to that heavy 6.2. I would be interested to see what your measurement is.

Thanks for the measurements and pics of your trimming. Makes me feel better about clearing that exo tubing on the slider.
 
Not a whole lot of progress lately, but some. I did get my front leaf springs ordered from ORD and they should be about two more weeks out. I also ordered ORD's Front Upper Shackle Hanger (FUSH), super shackles, all new bushings and greaseable bolts.

The super shackles are plated steel and I choose to paint them red. The FUSH kit comes painted a hammered gray. It was flaking off as soon as I got them so I blasted them and primed and painted them black. While I was at it I painted the 14 bolt pinion guard red that was orange.

Here they are drying.



Greaseable bolts and bushings



Also picked this up for getting out those pesky factory rivets and it is a good excuse to buy a new tool.



I also got my new billet "reverse" pattern shift knobs for the atlas twin sticks

 
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