Jeepskate's Joint

Home
About Me
Links
Trail Run Pics
Tech Articles

Jeepskate:
Suspension
Steering
Drivetrain
Body/Interior

Jeepskate II/XL:
Suspension
Steering
Drivetrain
Body/Interior

1 Last 7:
Suspension
Steering
Drivetrain
Body/Interior

 

Drivetrain

The bulk of the drivetrain remains unchanged from Jeepskate. I re-used the 4.0 (however I replaced the stock motor mounts with MORE Bombproof mounts that I got when they were having a holiday sale) and T-999/32RH along with the Dana 300 t-case and Dana 44 axles. So, I'll pretty much just be highlighting the changes here, rather than reiterating what has already been covered in the drivetrain section under Jeepskate.

Since the stock motor mounts are prone to failure and a good price was available, I bought a set of M.O.R.E's Bombproof motor mounts. These things are beefy!! The brackets on the engine are retained and new brackets supplied in the kit are bolted to them. The frame brackets are removed and new brackets supplied in the kit are bolted on in their place. The mounting scheme is similar to that of a leaf spring with the attachment of the two sets of brackets consisting of spring eye type bushings and bolts. The trade-off for this more secure mounting method is that more engine vibration is transmitted through the Jeep. Fast forward to Summer 2005 with the Scrambler disassembled again and I decided to go ahead and take the V8 plunge...I figure it's now or never. So, I sold off the 4.0 and associated parts & accessories and picked up a 360/5.9 out of a '92 Dodge Ram Van complete with the full vehicle harness and PCM. Anders and I collaborated on a custom engine cradle for it.

The trans will remain unchanged for the time being. It currently is essentially stock with the addition of a Mopar extra capacity pan and B&M shifter. I'm planning to add an external fluid cooler and may eventually install a Trans-Go shift kit (have it in a box in the garage). Fast forward to Summer 2005 and I had to switch trannies to go with the Mopar 360. I picked up a TF904 from a Duster. I will have it rebuilt with the lower first gear and heavier duty parts out of a spare T999 that I have as well as swapping the output shaft and output housing over. It will still get a shift kit and I'll probably use a Moroso trans pan since it holds more fluid than the Mopar pan and has bungs for temperature senders.

I've thought a lot off and on about gearing options and trying to build a Jeep that's suited to many different terrains & types of wheeling. Now obviously the 'best' solution would be a 3-speed transfer case, but there's nothing like that on the market right now (I'll bet someone's working on one by now...update Summer 2005 Stak now produces a 3-speed transfer case...one will probably eventually make it's way into Jeepskate II\XL when I don't have a bunch of other stuff to spend money on). I had considered a 4:1 low range kit for the Dana 300, but didn't want to give up the 'normal' low range since I won't always need to crawl. I also looked at the Klune-V under-drive and while it's an excellent solution, it's a lot of coin (about $1800) to drop at once. I had seen 'doubler' kits for GM drivetrains for mating the range box from an NP-203 to an NP-205 and seen a few one-off units made by machinists for other combos and wished that something like that existed for the Dana 300. Well, obviously other folks were thinking the same way and a couple have finally made their way to market (being able to take advantage of advancing technology has been one benefit of this protracted project). My 'final' plan became to use an NP-203 range box, 'doubler', and the Dana 300 with a 4:1 low range. The NP-203 range box gives me my 'normal' low-range (not quite as low at 2:1 vs. the Dana 300's 2.62:1, but it'll do), or I can leave it in high and utilize the new 4:1 in the Dana 300, or drop them both into low for some serious crawling. I picked up a rebuilt NP-203 off of Ebay and got an Advance Adapters doubler kit on sale from Scott at RockBuggySupply. Now, the trick with the AA kit is that it's made for their Atlas transfer case which is loosely based on the Dana 300 and shares the same bolt-pattern. It requires the additional purchase of a 10-spline input shaft and comes with a clocking ring (so I sold my Xtreme ring). I also stumbled across a sale on Tera products at DC's 4WD and ended up picking up a 4:1 low range kit and heavy duty 32-spline output shaft delivered to my door for far less than the 4:1 typically sells for alone. The whole setup ended up costing me about $1200 spread out over about 3 months, plus I'll make a few bucks back selling the 'old' clocking ring. Then I saw that JB Conversions was offering a heavy duty 32-spline front output, so I picked up one of those along with their heavy duty shift rail springs and some misc. bearings and seals. A couple of months later, I stumbled across a guy selling parts from a Dana 300 on Ebay, so I grabbed the case and shift rails & forks...I'll be putting all of the new parts into this case and will keep my existing Dana 300 as a spare. I'll add details and pictures as I work through the install. I may also look into a Roark FabWorks rear output support for the Dana 300 to help hold everything up and reduce the strain on the tranny. And of course I will need to build a custom crossmember/skidplate. Fast forward to February 2006 and I came across a group buy deal on the JB Conversions LoMax 4:1 kit. There have been scattered reports of TeraLow breakage, and I was a little concerned given the added stress of a V8 and a doubler, so I sold the TeraLow and bought the LoMax for just a few bucks more after the owner essentially dared anyone to manage to break his 4:1 kit. Also in 2005, Advance Adapters released a cable shifter kit for the Atlas and it wasn't long before folks started retro-fitting it to Dana 300's, fabbing their own, and a couple of other vendors (Whaley Enterprises & Northwest Fab) released kits. I'm putting my own together with some heavy duty push/pull cables I picked up cheap off Ebay (one is a military t-case shift cable) and fabbing up my own shift levers capped with pistol grip shifters. Anders and I collaborated on a custom belly pan/crossmember to support & protect the whole shebang and will be fabbing up a cockpit style console to mount the shifter in. Anders fabed up a custom tubular crossmember/belly skid which attaches to the frame via plates with ears that are welded to the frame and tubes with YJ spring bushings in them that bolt to the ears. We were able to retain the stock auto trans mount and torque arm. We went through about 3 different designs & mock-ups before the final version that you see here. It will be skinned with a mix of welded & removeable panels. Anders also fabbed up a Dana 300 rear output support to fit the JB rear output when Roark failed to produce one in time. This takes some of the weight & leverage off of the trans tailhousing which would otherwise be supporting both the Dana 300 and the NP-203 range box.

I retained the Dana 44's from Jeepskate with the addition of some Performance Tire & Wheel 1.25" wheel spacers on the rear to get the track-widths a little bit closer. I've got a Ford 9" out of a Lincoln Versailles sitting in a corner of the garage that'll probably eventually replace the rear Dana 44. I still haven't made a final decision on gears & lockers. Right now I'm running 3.73's and a rebuilt Trac-Loc out back and have a couple of empty carriers, 4.10 gear sets and an EZ-Locker sitting in boxes. I may leave the 3.73's alone since I've got the dual t-cases, put the EZ-Locker up front, and replace the rear Trac-Loc (probably put it in '1 Last 7') with either an Aussie Locker, Detroit Locker, or Detroit Elec-Trac. I'll be adding diff guards (have a 4xDoc sitting in a box) as well. Fast forward to Spring/Summer 2005, I sold the rear Dana 44 to my buddy Grub for the rear of his Scrambler that I've been helping him build. Figured it might not be up to the task with the doubler. I picked up one of those odd-ball semi-float Dana 60 housings out of Ohio off Ebay for cheap. The housing ends are like J-4000's and I have a couple of buddies who are running those, so I went down to Zach's farm and he gave me all of the bearing & seal part numbers, let me borrow his spacer and bearing retainer plates to get specs off of, and let me borrow a shaft to send to Moser as a sample. I sent the stock shaft down to Moser along with my spec sheet and had a set of custom alloy shafts made. I bought a set of 4.10's and a Detroit Locker to stuff the pumpkin with. I stuffed the front 44 with a set of the 4.10's I already had and a Detroit Elec-Trac that I picked up cheap off Ebay. The guard for the actuator that comes with the Elec-Trac isn't mounted in a particularly beefy manner and the manual even recommends using a better guard for heavy off road use. I stumbled across Skinny Pedal Performance on Ebay while looking for some guards for the 30/44 combo in 1Last7. I bought those and was pleased with the beef and saw their Dana 60 guard and that they offered custom services, so I approached them about building a guard for the Elec-Trac. They agreed, so I sent off the cover and actuator along with the stock guard and they built me a custom beefy guard that protects the whole diff cover as well as the actuator...I bought that and their Dana 60 guard. New perches were welded onto the Dana 60 and a custom bolt-on over-the-top axle truss with integral bam-bar anti-wrap bar mount was added. The addition of the bam-bar also required adding an additional crossmember to the frame to attach the front of the bar to.


Bombproof...
M.O.R.E engine mounts painted with grey Hammerite.


Rockin' the cradle...
Mopar 360 sitting in the Xtreme Drivetrain & Suspension engine cradle with removable oil pan skid.


In Range...
Front 'range box' removed from a Dodge version NP-203.


Match Maker...
Advance Adapters Atlas/NP-203 doubler kit.


Double up...
Final positioning of the doubler setup and custom crossmember.


Double-crossed...
Nearly completed (needs skinning) crossmember/skid...note the custom Dana 300 support bracket.


Truss-worthy...
Over-the-top bolt-on rear truss with bam-bar mount & additional frame crossmember for bam-bar.