Foamy Tranny Fluid!!!!

[HotRodPC]

Sooooo, I'm assuming you have the NP203 Full time transfer case as of right now with a Th350. Are you wanting to keep the full time transfer case? Most usually want to get away from that. Now might be the time to get away from it. Keep you eyes open for a used working Transmission and Tcase combo. We don't know what your plans are or budget is like for this truck. Might be a good time to fire up an Under Construction thread on your truck and do some splainin' on what you want to do with it.

Not sure how mechanical you are, or what your experience is with transmissions, but you can do a stock rebuild on a Th350 for less than $100 for your rebuild kit and trans fluid of you do it yourself.

 

[tiredtiretodd]

Post up some pics of your tranny and transfer case

I'll post up some picks of my tranny and transfer case soon, I haven't had the time to do it! I have a TH350 tranny and a NP203 transfer case.

 

[tiredtiretodd]

Sooooo, I'm assuming you have the NP203 Full time transfer case as of right now with a Th350. Are you wanting to keep the full time transfer case? Most usually want to get away from that. Now might be the time to get away from it. Keep you eyes open for a used working Transmission and Tcase combo. We don't know what your plans are or budget is like for this truck. Might be a good time to fire up an Under Construction thread on your truck and do some splainin' on what you want to do with it.

Not sure how mechanical you are, or what your experience is with transmissions, but you can do a stock rebuild on a Th350 for less than $100 for your rebuild kit and trans fluid of you do it yourself.

I would like to switch to a NP205. My co-worker has a TH400/NP205 that he wants $500 for I'm going to tell him to let me install it and if it works I'll give him $500 for it. Will the drive lines work with the new setup? How do I start a under construction thread? I've always wrenched on my own vehicles but I've never worked on a tranny. I do own a Haynes manual on my square and i've been able to use that to do a lot of work on my square. I buy them for every vehicle I've owned and i've saved a lot of cash on repaires! I'll probably buy the TH 400 and NP205 and then try to rebuild the TH350 just to get the experience.

 

[MadOgre]

I would like to switch to a NP205. My co-worker has a TH400/NP205 that he wants $500 for I'm going to tell him to let me install it and if it works I'll give him $500 for it. Will the drive lines work with the new setup? How do I start a under construction thread? I've always wrenched on my own vehicles but I've never worked on a tranny. I do own a Haynes manual on my square and i've been able to use that to do a lot of work on my square. I buy them for every vehicle I've owned and i've saved a lot of cash on repaires! I'll probably buy the TH 400 and NP205 and then try to rebuild the TH350 just to get the experience.

I really really REALLY like the TH400. I would pay $500 for that th400/205 if it works for sure!

Make sure you get the cross member for the TH400. Now maybe the 203 uses the same cross member Im not sure. But now that I think of it, It probably does. Just make sure it does or else get the one for that TH400

Its really simple just will take some time.

Just go to the thread categories via the search box on the lower right side of the screen page and then at the top left of the screen page of the category that suits your thread you will see a box that says start new thread, click it and post.

 

[HotRodPC]

No, the driveshafts will need to be worked over. They'll be different lengths, and maybe even different types. Does this NP205 have the slip yoke or the fixed yoke? If it's not a slip yoke, you'll need a driveshaft with the slip in it. There also is 2 different Th400/NP205 adapters, a short and a tall, That'll make the difference in which crossmember you'd need. Hopefully it's the same and matches the the NP203 which a good chance it will. Trans cool lines and linkage for the trans is not a problem. Vac Modulator hose will need to be worked out a little bit, but that's not big deal. Th350 had the Vac Modulator in the rear, the Th400 has it on the side up closer to the front.

If you're willing to tolerate the minor disadvantages of the Th400 and the NP205 then you'll have the benefit of what's considered bulletproof. The NP205 is certainly an upgrade over the NP203 in all aspects. Though the NP205 only as a 1.9 crawl ratio in 4Low. Some find that a big disadvantage, if you don't need a low crawl ratio, then there's no problem. It's a very strong gear to gear driven cast iron Tcase. Heavy as compared to an NP208 but it's not heavier than the chain driven full time NP203, so it is a worthy upgrade. If I was running a 3 speed auto and didn't need Overdrive, I'd certianly run a Th400/NP205. I do happen to have a Th350 that slips and the NP205, crossmember and driveshafts that I might run someday.

I really like the option of the Twin Stick on an NP205 too. If both of those are in good working order, $500 is probably a pretty fair deal.

 

[tiredtiretodd]

Can't wait to get it and put it in! Pun intended! I'm fortunate that my coworker isn't actively trying to sell it. I'm going to make him an offer he can't refuse.

 

[MadOgre]

I hope it doesn't have anything to do with putting it in!

 

[tiredtiretodd]

My co-worker agreed to let me take the tranny and t-case and install it. I'd really like to pair the NP203 to the NP205. Would that mean that I would be able to keep that NP203 crawling gear?

 

[CSFJ]

If I understand correctly, you would use the low range box from the 203 in front of the output for the 205, thereby multiplying the 2:1 low of the 205 by the 2.3:1 low of the 203.

 

[HotRodPC]

My co-worker agreed to let me take the tranny and t-case and install it. I'd really like to pair the NP203 to the NP205. Would that mean that I would be able to keep that NP203 crawling gear?

It's expensive to get the adapter to marry the 2. It's called using the NP203 as a Doubler for your NP205 Crawl Ratio. And yes, it eliminates the chain in the NP203 and the NP203 bolts directly in front of the NP205, and the NP 205 being gear driven, you keep the gear driven all the way through.

As far as ratio's both the NP203 and NP205 are both very close to 2:1 ratio. So here's what happens, If you use your NP205 in 4Low, you get the 2:1 ratio. By splitting it again and putting the NP203 in 4Low or Crawl, you just multiplied it by 2 again, so now you have a 4:1 ratio. It's a nice option if you need it and can justify the expense of the adapter and the mods to the driveshafts, then I'd also Twin Stick my NP205 which means a Triple Stick Transfer case with unlimited options. 1 Stick for the Doubler (NP203) it's either 1:1 or 2:1. Then the 2 sicks for the NP205, One for the High Range 1:1 or Low Range 2:1, and the other stick for Front, Rear or Both axles engaged. So you would have the option to select a 1:1, 2:1 or 4:1 Front wheel drive only option, Rear Wheel Drive only Option, or Both Axles.

 

[tiredtiretodd]

update! I moved my square so I could weed eat my yard and decided to take it around the block. I took it up to the point where it needed to shift and let off the accelerator and it shifted. this is after it sat for a few weeks and leaked a couple quarts of fluid.

 

[HotRodPC]

Sounds like it could be a vac modulator. On a Th350, there is only 3 things that determine shift points. Vac Modulator, governor and detent cable. All which can be checked without pulling the trans and easy to get to. Don't even have to remove the pan unless the detent valve is hung up but not likely the problem anyway.

 

[tiredtiretodd]

Thanks for all the info HotRod, it's been frustrating and fun all at the same time! I do need to get a new pan. i already have a new accelerator cable so I'm going to get a new kickdown cable and the bracket that works with my Edelbrock carb.

 

[tiredtiretodd]

Governor

Sounds like it could be a vac modulator. On a Th350, there is only 3 things that determine shift points. Vac Modulator, governor and detent cable. All which can be checked without pulling the trans and easy to get to. Don't even have to remove the pan unless the detent valve is hung up but not likely the problem anyway.

If I want to check the governor is it easy to remove? I heard that there is a plastic gear on it......Is this true? Seems like it would need to be replaced at some point. I'll look into it just to be certain. I did put more fluid in it, after tightening the bolts on the pan a little more since it leaked a bunch out over the last couple weeks. The bolts on the pan were only snugged down the first time.It didn't leak at all over night that I could see. I also used Lucas Transmission Fix, just to have a thicker fluid in it.

 

[HotRodPC]

The governor is inside the round dome cover on the driver side of the case. Use a screwdriver and light hammer to tap the cover off. The governor will slide right out. It's not spring loaded or anything like that and easy to do. Straight forward process. It will be normal to lose up to a few tablespoons of fluid when you take the cover off.