Another NP208 NP241 Clocking Thread!

[TerryD]

Well, my yearly wheeling trip is done and I'm about ready to start slicing the floor boards of the K5 up and turning the t-case on it's ear. I'm wanting to clock it as flat as possible so I'm going to start by slicing the floor board, then putting in the case in the top position and seeing how it fits, then possibly dropping it if I think it's too flat or a lot higher than the frame rails with no gain since the cross-member is the snag point now. Before I get started with that, I had some questions for guys who have done this before.

Firstly, I would really like to keep my factory seats for the time being and needed some input on how to get the mounts fixed up so that it will still tilt forward so the kids can get in the back seat. In the future, it will get a cage and seat bars and this won't be an issue, but right now it gets driven on the street more than the trail I like to take the family out in it.

Second, I'm only on 2.5" lift and looking to go as flat as possible with the t-case and I'm wondering what issues I'm going to run into with my front driveshaft. I may possibly be going to ~4" lift in the future as well, but I have not made my mind up on that yet.

Third thing is oil fill. Do I need to just put the factory required amount of fluid in it or is this a less-is-more thing? It will be driven where it goes so I need a good idea of how much fluid to have in there to get it to live on the street.

 

[TerryD]

Welp, no answers means dig in I guess! Working over quite a bit this weekend because of a boiler outage at work (most of my area is offline for a week) so progress is slow. Julie took the kids to her sisters for my nieces 18th B-day party and since I managed to get just enough shifts to ruin the weekend, I decided to get a start on this.

After work this evening I stripped the old patchwork exhaust off, get the passenger seat, console, t-case shifter and transmission tunnel cover off before it got too dark to work anymore. I obviously had to do a quick start-up after the exhaust was off though.

I'm hoping to get the driveshafts, t-case and cross-member out tomorrow evening.

I think I've got a plan to keep the factory front seat for now. We'll have to see how it goes when I get to that part.

 

[K85 Octane]

Ok, give me a moment and I'll answer some of the questions. Also, I'm gunna PM you my phone number. If you text message, I can text back and answer or even a picture pretty quickly. (except during the week, pictures would have to wait till after work)

 

[K85 Octane]

Ok, pages 58 & 62 of my build are full of my dealings with clocking my 241.

Going to try answering your questions in the first post. Hope I don't miss anything, just let me know. I might reply in steps too.


First thing I'd like to say is......body lift. Do a 1" body lift if you don't have one already. This is going to be so much easier with it. I can't comprehend the PITA you'll experience with the trans tunnel and T-case linkage if you keep it stock. Look at this picture and you'll see what I mean. There is no room for tools or hands.

The passenger seat can be left in place easily. Just be careful where you cut. The bracing for the front mounts is RIGHT IN THE WAY. I don't have original seats but I am using the front bolt holes. If you cut little by little, you should be able to save the mounts. In this picture, you can see a bolt hole drilled next to the opening. The original mount is gone, only a couple inches back from this this hole. If you look real hard, at the right side corner, you can see part of the mounting hole.

 

[K85 Octane]

PS> even if you save the front mount, consider beefing up the area since it will want to oil can and dent with the new giant hole.

 

[big dan]

I have one in a k10 clocked up 1 position and one in my scout clocked completely flat as high as it will go. Both vehicles are a little different then yours so I cant help much on body mods but the drivetrain is similar so I can name some issues you'll have.

On my k10 I went one position, just higher than the bottom of the crossmember. Did that because I don't plan on changing the crossmember so I didn't see any reason to have all the troubles without really gaining any clearance. Have a 4 inch lift and factory dual cardan front shaft with the stops ground out. Even got the factory linkage to hook up and exhaust cleared.

Now my scout is a different story. Aside from body mods which wouldn't matter to you any way, nothing factory worked. I used a short adapter and built a crossmember for a flat belly, its pointless to clock it all the way up unless you plan on going completely flat.

Factory chevy shift linkage didn't work, didn't even come close. Had to build a shifter, move it toward the center of the tranny hump and build the linkage. Also had to shorten the factory np208 shift lever on the t-case. Its kind of hinky but it works.

For exhaust, small block long tube headers wont fit my setup anymore. My front driveshaft ran right into the exhaust flange, and Im not talking bumped a little, the driveshaft yoke at the t-case and header flange occupied the same space. I used block huggers and ran a tube straight down, under the oil pan and ties into a y-pipe on the passenger side.

For driveshaft the dual cardan joint with stops ground way out was maxed out at ride height, which again will be different for you but similar, my scout is very close to a blazer/truck with a 4 inch lift. I used a high clearance 1310 yoke (its what I had) with a single u-joint on each end. Works good but I don't have a lot of flex, plus my shackle is on the other side of the spring so my driveshaft gets longer making the angle better when it droops. There are some older threads I researched about this and some guys are having good luck with single 1410 joints and some used dana 60 axle yokes which give lots of clearance.

Oh, and for oil, I just fill till it reaches the bottom of the fill hole. Never really paid much attention to what it calls for. But my scout doesn't see a lot of street time and when it does it never really makes it past 40-45 mph plus it spends most of its time at awkward angles so I figure more is better.

 

[K85 Octane]

Ok, to give you an idea of how high up my T-case is.... I am running the factory tranny mount. If you run a straight edge from rail to rail, the tranny mount is about 3/16-1/4" above it.

 

[TerryD]

Awesome! Thanks. With the condition of my truck, I'm not sure that a body lift would be possible. I doubt any body mounts would come loose without having to rebuild the entire are around them to put them back. I will keep it in mind if I start having issues though. It's not out of the question, but seems risky at this point.

My idea about the seat mounts now involves cutting out the entire floor between the tunnel and the outter seat mount and raising that section of floor up 3-4" and building up to it with new metal. That will create a tunnel for the front output and give me plenty of room and flexibility in mounting the seats. Since I'm running the older style seats, I'll just have to move the front seat pivot point up closer to where it bolts to the seat.

I've been stewing this over for some time and since I didn't get any replies, I checked it out this evening while pulling stuff out and I think it'll work out good. Since I like to move the rockers up a bit in the future to improve clearance as well as eliminate most of the rust easliy, floor mods are impending so it can all be changed in the future.

 

[K85 Octane]

I run a Tom Woods front 1350 CV shaft with 1350 axle side. So far everything clears. I'm also running 5" of lift with my front axle pushed 1.5" forward. I don't think my driveshaft would work if I didn't have the axle forward. My CV is very close to binding at full droop. The axle being forward helps with angles.

I don't see you ever having a problem with a 2.5" lift if you grind the CV ears or get an aftermarket shaft. Also, if you fully clock the T-case but drop the drivetrain down to clear the floor, there will be a bunch of new problems with this. (ONE) the rear driveshaft angle will change. This might not be bad for a high lift, but with a 2.5" lift it might get weird. (TWO) As the front T-case output essentially rotates up as it drops, this will put the front CV at an even more nasty angle. Consider the front flange, now pointing upwards a tiny bit with the driveshaft making a hard "U-turn" towards the axle. Just makes things worse.

 

[K85 Octane]

Here is a shot of my linkage. The rod coming off the shifter goes back straight. The rod connected to the T-case is turned slightly to the driver's side. This was to prevent binding on the T-case side. When the T-case moves up, obviously the linkage has to move up too. But it also moves towards the driver side.

So looking at the picture, you can see I raised the linkage with the plate I welding in and cocked the linkage to the driver side a little.

I also had to do a little grinding on the rod that enters the T-case arm. It has a small "ridge" or "flange" that is present in the picture. That "flange" also binds against the arm. I tried changing the linkage angles but it always bound up at the flange. So out came the grinder. I still use the rubber grommet thing, but now the linkage is free to move in the arm a little more. I truly feel my shifter feels just as good as stock.

 

[K85 Octane]

My clocking ring is from Kurt. I recommend either welding up the holes you aren't going to use or put some RTV in them and allowing it to dry. Cut off the excess, use a whole bunch of "The Right Stuff" RTV, and mount.

Also, be careful as you tighten the nuts for the mount. The studs can easily turn with the nuts and bite into the T-case's aluminum easily. Not very cool. I think the studs have an allen head IIRC, which helps, but can be difficult to get to. If it's possible, install the studs and pin them so they don't continue through the holes and into the aluminum. Then RTV the hell out of it and install.

 

[TerryD]

Got my Right Stuff, ATF, and a new seal for the rear output. Gonna clean it up a bit and do a little mock up. Figure out if I want it all the way up or the notch before.

What do you guys do about fluid level? I still want to street drive this thing so I don't want to overfill or underfill it. I found a spec on AMSOIL that says 4.4 pints for a 90 NP241C. Does that sound right?

 

[K85 Octane]

No shop manual?
If that amount comes back as correct, good, run it. With it clocked, you can't really just dump fluid in and wait till it dribbles out. I think that was done once with mine and I ended up blowing fluid out of the vent. I extended the vent into the engine bay and let a little fluid out.

 

[TerryD]

I don't have a shop manual for the K5. I probably should, but most of it is pieced together and fairly simple stuff so I haven't bothered hunting one down. Anyways, I think I could possibly get the t-case in this weekend and get the crossmember started, maybe even welded. We'll have to see how it goes when I start. I have a basic idea of what I want, I've just got to tweak it as it goes I guess.

 

[TerryD]

So I got to checking out the NP241 and the chain is pretty worn in it. I have not found evidence of it skipping teeth yet but that's just looking through the drain and fill holes. My NP208 is a lot tighter than this so I'm in the fence.

Is it a big deal to throw a chain in a NP241 basically laying on the ground? I know it's got to be clean and all but wondering if it can be done.

Also, the rear output housing it's cracked at it's flange around two of the four bolts.

I'm thinking throw a chain in it now and maybe a SYE member has a good tail shaft housing laying about I could get cheap. That'd get me going I believe at this point.

I may mock up with the 241, then throw in my 208 and see if I need any drastic cross member changes to run my 208 for now and save the 241 for a rebuild, SYE, and swap down the road.

 

[TerryD]

So I'm not as stout as I was a few years ago. Took two good tries to get the 241 and adapter in. First one almost ended badly. Anyways, got a fair amount of clearance out of it I think. I'm not going to be able to use the strut rod without some interesting reworking.

CV is maxed out too right now at rise height. Gonna grind the stops and see how it works then.

Cross member looks to be an interesting feat at the moment but I have an idea.

 

[K85 Octane]

Support rod is easy, just add a piece of steel like I did, don't over think, it's just to hold it from moving forward and back, not up and down.

Now that it think about it, I have no idea where my old tail cone is

208 and 241 will swap easily, even after the crossmember build etc. make sure to keep external shift arm from each, I have two different ones and have no idea which is what. My 208 SYE total length was 3/4" longer than my 241 standard JB SYE, that helped with the added thickness of the clocking ring.

 

[TerryD]

My progress for the day. I hope to get some room so I don't have to drag everything out and can just work it from were it's at.

The wind ruined a couple welds I had to grind out and rework so there was some delay. Then having to measure three times and cut once because I have limited materials right now.

Not bad. The mount bolts to this. It'll be the middle of the cross member. The tube to the drivers side will be straight. The passenger side one will either bend back under the output flange and back forward in a near 90* bend or a may wuss out and put a u-bend in it to just give some clearance under the CV.

 

[ryoken]

nice fishmouths..

 

[TerryD]

Thanks Paul. I cheat, I have the $20 HF notcher. It took me a good 20 min today to get it to cut square and centered, but it worked out ok.

We used the poop out of one on my buddy's F150 build so I figured it'd be worth it to have one. I've got to get my dinosaur of drill press going so I can mount it in there, then it'll do even better. This was done with it clamped too the bumper of my K5 with my 1/2 B&D drill.