So, that's why it was leaking so much today!

[Yukon Jack]

Ran some ladders over to a buddy today and saw an unusual amount of oil under my leaky Rockwell T221 transfer case. I'm guessing I got low on gear oil (been awhile since I topped it off).



Looks like it took out the bearings on the input shaft. Anyone have experience with this that can let me know what I'm in for repairing this.

I do have an NP205 that I can swap in. Probably want to do what is the simplest route.

[OLDCHEV4X4]

I never had a Rockwell, But i hear parts are hard to find and expensive.
Since you have a 205...Looks like it might be time for a swap.

[griesel72]

is that just a wear and tear item, or is it due to your horsepower?

[Yukon Jack]

I wish I could say I was giving it hell on some nasty trail, but alas, those occasional drips on the ground added up to low gear oil which Rockwell's don't think to highly of.

[BLAZERMAN]

If you decide to rebuild I have an NOS bearing retainer.

[Yukon Jack]

I know this has been posted before, but here is a link to an exploded diagram and maintenance/rebuild info on the Rockwell T221.

I'm still investigating what all is involved with replacing that bearing on the back side of the input shaft.

Am I correct in assuming this is a repair that needs to be done with the transfer case removed from the vehicle?


Also, here is a great thread I'm reviewing concerning issues with swapping an NP205 in place of the Rockwell.

I know two boardmembers who are going to be getting some questions for me - 1969 GMC and Jakes 68GMC

[68,69 K20]

Originally Posted by Yukon Jack

Also, here is a great thread I'm reviewing concerning issues with swapping an NP205 in place of the Rockwell.

I know two boardmembers who are going to be getting some questions for me - 1969 GMC and Jakes 68GMC

Make that 3, I have a 205 I have been thinking about swapping into my 69K20 in place of the Rockwell.

I would go with the 205 for now, but I agree with special k, keep the Rockwell, rebuild it at your lesiure. You may or may not want to bring it back to orig condition some day and if you do and you got rid it it, you'll be kickin yourself.

[special-K]

Are you swapping?I know where a couple of Rockwells are sitting in PA.You might be able to get parts from one.I understand if you want to sawp.Prolly easier and cheaper in the long run.But,I wouldn`t scrap a Rockwell t-case.It can do someone some good on down the road with an original resto.

[Yukon Jack]

Probably want to do what is the simplest route.

I do have a spare Rockwell sitting in my shop along with a spare NP205.

I know the NP205 would require making a new hole in the hump and with carpet I would have to either do a patch or replace the carpet. The carpet is very new and I doubt a patch would look very good.

From web researching today I see the NP205's crossmember sits 1.5 inches back compared to the Rockwell's crossmember. I also see that the NP205's crossmember is 1" deeper (the transfer case sits 1" lower). I also see that some driveshaft length adjustments may well be necessary.

One of my goals in the near future is to get rid of some of my truck's body lift. I had to increase the body lift to clear the bbc when I swapped it in.

One option that I have been considering is moving the engine forward and also dropping the engine down a touch. Moving the engine forward 1.5" to 2" probably gets me the necessary firewall clearance to get the body lift reduced down to 1-2".

So, I haven't put a tape measure to all of this, but maybe I could leave my transfer case crossmember where it is and put in the NP205 and move the engine forward - thereby killing two birds with one stone. The reduced body lift will probably allow me to avoid needing to drop my existing crossmember down 1", unless I need to do that to keep the engine sitting at a proper angle, and I guess I need to consider if that causes any driveshaft angle issues.

My other winter project that plays into this is I'm swapping a Dana 60 soon - that might require front driveshaft lenght adjustments too.

Lots of issues, feel free to chime in with thoughts and recommendations!

[jamie72]

imo it really don`t `look` too bad, i would think just patching it up would be alot cheaper-easier thing to do??
besides the leak is there noise - vibration??

[special-K]

I was wondering if you could run it awhile with a new cap,too.

[msgross]

JB Weld? just kidding... I hear a full truck rebuild in process though! You know how it starts... and then ends with rockwell axles, supercharger etc...

Good luck, do a writeup with either route you go, would be good for us rockwell guys...

[jamie72]

Originally Posted by msgross

JB Weld? just kidding... I hear a full truck rebuild in process though! You know how it starts... and then ends with rockwell axles, supercharger etc...

Good luck, do a writeup with either route you go, would be good for us rockwell guys...

i wasn`t thinking jb weld... you hoosiers... bubble gum...j/k
a new cap and maybe bearing?? got anything loose in it?

[Yukon Jack]

Definitely needs a new bearing as the race is in pieces in there. By gawd it got me home 5 miles from my buddy's house so I'm pretty sure nothing is messed up very badly except for the bearings and race.

I'm sure leaning towards doing this the simpliest/easiest way.

I think I will get that bearing cap pulled and take a peak in there and see what's what.

Anybody know the answer to whether this is a repair that requires the t/c to be removed?

[Yukon Jack]

Oh, don't worry, the Rockwell won't get trashed regardless of what I do, I have a bad habit of keeping everything I remove, well, except for that bit of firewall I had to cut out to fit the bbc. Hmm, I did keep part of that too

[special-K]

I`m picturing the repair,here,and I`d think you could do it "in truck".It may be worth the effort to remove it to set it on a bench.

[Yukon Jack]

Get ready for probably more info than your interested in reading:

Spent about 30 minutes in the shop last night pondering my options and getting some measurements.

Here is a pic of one of my NP205 setups and another pic of one of my Rockwell T221 setups with measurements of their differences.





If I installed the NP205 right where the T221 is positioned it looks like that would move my motor and transmission forward 2". In looking at my firewall, moving the motor forward 2" possibly could allow me to remove 2" of the body lift. That is one of my goals. Moving the motor forward 2 1/2" would definitely allow me to remove 2" of the body lift.

I do note that putting in the NP205 will give me a slightly longer front driveshaft and while I didn't study the postion of the front yokes, that might help get rid of some of my front driveshaft angle.

You may remember I used 4 washers (3/8" total) per motor mount bolt on the passenger side and 2 washers (3/16" total) per motor mount bolt to raise the engine slightly for oil pan clearance. Removing those will help with my firewall clearance on the drivers side since that in effect has the motor sitting a touch higher than it should be and about 3/8" closer to the firewall than it should be. If I remove those washers I anticapate removing the engine crossmember and cutting out the area that is too close to the oil pan then putting in a flat piece of metal angled to fix that problem area.

I do see an issue with my rear driveshaft. My present setup uses a carrier bearing. As you can see from the pic of the T221, the rear output for the rear driveshaft is very low, while the rear output is high on the NP205. I'm not sure what the maximum length a rear driveshaft can be, but maybe an option would be to get rid of the carrier bearing and have just a one piece rear driveshaft. My carrier bearing has maybe 1000 miles on it, but no big deal.

I'm low on truck funds at the present time so that is going to play into my decision. Additionally, I hurt my lower back in October and just rolling around on my creeper and climbing into the 69's engine bay one time had me hurting so I'm unfortunately pretty sure this will be a painful project, regardless of what I decide to do. Either way I have to pull the transfer case.

Dang, after typing all that I need more coffee

[1969K10]

Dude, I feel for you. Just got done doing this swap this winter. Needed a longer front drive shaft, and to shorten the rear. Re-used & re-located the 221 x-member. Made a new x-member for my carrier bearing & relocated. I got very lucky, and my exhaust did not require modifying, but sure looked like it was going to need it. Also had to aquire a new adapter between the X-fer & tranny.

I really liked my 221, but I don't miss the constant back ground noise of it. Once I get the shifters for my 205 working correctly, I think it'll make a nice X-fer.

[milled]

Originally Posted by 1969K10

Dude, I feel for you. Just got done doing this swap this winter. Needed a longer front drive shaft, and to shorten the rear. Re-used & re-located the 221 x-member. Made a new x-member for my carrier bearing & relocated. I got very lucky, and my exhaust did not require modifying, but sure looked like it was going to need it. Also had to aquire a new adapter between the X-fer & tranny.

I really liked my 221, but I don't miss the constant back ground noise of it. Once I get the shifters for my 205 working correctly, I think it'll make a nice X-fer.

Here's a thread I started in a diesel forum. All about what you guys have.
http://www.4btswaps.com/forum/showth...?t=3189&page=2

[Blue_71]

i dont know for sure on the carrier bearing deal, but my K20 has a one peice rear shaft... its a 4" tube. the local driveshaft place (only one in a 200 mile radius with a balancer) looked at it and told me id be fine with a 3" for the length ive got. this is a 350/SM465/NP205 truck

[LSGarage]

I've got my T221 apart on the bench right now. From what I can see in your photo that is just a cap only. It doesn't contain the bearing, that's sets in the TC case. I think I would try to find a replacement cap or have one made and that may fix your issue. That cap on my appears only to hold the bearing in the case and seal up the end of the shaft. I don't believe that this cap had any shims on it either. My 2 cents.

[Yukon Jack]

1969K10, got any pics you could post of the carrier bearing as it is positioned now?

Did you have the short portion of the 2 piece driveshaft shortened, or the portion that connects to the rear axle?

Did you have to drop your transfer case crossmember any or just move it back?

Thanks.

Oh, to add insult to injury - was driving the 70 K5 last night on the way home from work and the darn thing died about 3/4 miles from home. That "what is wrong" post will be in the Engine & Drivetrain subforum.

[1969K10]

Originally Posted by Yukon Jack

1969K10, got any pics you could post of the carrier bearing as it is positioned now?

Did you have the short portion of the 2 piece driveshaft shortened, or the portion that connects to the rear axle?

Did you have to drop your transfer case crossmember any or just move it back?

Thanks.

Oh, to add insult to injury - was driving the 70 K5 last night on the way home from work and the darn thing died about 3/4 miles from home. That "what is wrong" post will be in the Engine & Drivetrain subforum.

I can take some phone pics, that will be crappy...
I shortend the long, rear section of DS. fortunately, it was slightly bent, and he straightened it while at it. got rid of my vibration I couldn't ever find!
Just moved it back. If I was doing it again, I'd make a new Xmember that was a little shorter. the top of the X-fer doesn't hit (I think), but it's really close.

[Yukon Jack]

LSGarage, when I look inside the crack on the cover I see a loose piece of metal that sure looks like a piece of a bearing or race.

I will definitely pull the cover and inspect before I go any further.

Something that happened probably three times a while back may be related to this problem. I only drive this truck maybe once every week or two. About 1 1/2 months ago, on about three separate occasions, I would be driving no more than 5 to 10 mph and all of a sudden it felt like I had hit the brakes hard when I was not using the brakes. I assumed I had a brake shoe that was catching. I now think a loose piece(s) of metal was getting caught in the gears, causing the transfer case to lock up. Sure makes sense considering the current problem.

special-K, I do have the 1 ton's driveshafts and that is an option. Since I'm running a 14 bolt full floater, I probably would only have to swap out the front u-joint end as the rear should bolt right up.

[68,69 K20]

Originally Posted by Yukon Jack

Oh, to add insult to injury - was driving the 70 K5 last night on the way home from work and the darn thing died about 3/4 miles from home. That "what is wrong" post will be in the Engine & Drivetrain subforum.

Ouch!! When it rains it pours, Hope you get it worked out buddy!!