Advance Adapters NP435 to D20, looking for feedback

[Bundy]

I have an existing AA adapter NP435 to D20 which is stamped AA-1114 on the top. I am guessing this was one of the first versions of this adapter. It was leaking from the PO so i took it all out, cleaned it up and put new seals on.

Fast forward 6 months and it starts leaking again. I checked it out and all 4 adapter bolts to the NP435 were hand tight at best, as were two of the adapter to D20, and another one was half backed out.

I am almost positive i used lock tite on the bolts, but i suppose it's possible i didn't.

this adapter has some crude "custom" mods and none the bolt holes has enough room for more than a half turn- a real PITA to work with.

I am wondering if the newer revision adapter P/N 50-2700 has adressed any of the older adapter's shortcomings and if maybe these bolts coming loose could be the result of old technology.

If anyone has experience with this adapter, please give me some feedback!

 

[broncnaz]

I'm not sure what the number of my adapter is I'm sure its not one of the earliest ones but still fairly early did my swap in 86. I'm not sure if they changed anything up later on as making more room for turning bolts might weaken the adapter but I'm not sure. I'm pretty sure I cant get a box end wrench on my bolts either. I can check tomorrow.
I dont think I've ever had a issue with my bolts loosening. I do have a slight leak after all these years but nothing major doesnt drip just seeps a littel. Do you have lock washers under the bolts? Also even with lock tite the threads on both sides need to be oil free or it doesnt work well.

 

[Oatmeal]

I have what I believe to be the same adapter (cast aluminum, right?). Bought it and the trans, bellhousing, clutch linkage.........when I swapped from my C-4 to an NP-435. The problem is (with mine anyway) that there is no provision for the dowel pin between the adapter and t-case allowing movement between the two which eventually breaks the seal (the persistent leaks) and loosens the bolts.....no matter how much Loctite I'd use What I did was install studs in place of the bolts, put a slight taper in the holes on the adapter and beveled the nuts that I used to bolt it together with (picture a lug nut and the tapered hole in a wheel rim) and it seems to have cured the problem.......I Loctited them securely of course. It was so bad that I once lost 4 bolts and damn near the t-case on the freeway before I figured out what was going on Hope that helps!---------Hans

 

[Bundy]

I dont think I've ever had a issue with my bolts loosening. I do have a slight leak after all these years but nothing major doesnt drip just seeps a littel. Do you have lock washers under the bolts? Also even with lock tite the threads on both sides need to be oil free or it doesnt work well.

if you have the same adapter as me you should check the bolts, could be why it's leaking. I have lock washers and loctite!

The problem is (with mine anyway) that there is no provision for the dowel pin between the adapter and t-case allowing movement between the two which eventually breaks the seal (the persistent leaks) and loosens the bolts.....no matter how much Loctite I'd use What I did was install studs in place of the bolts, put a slight taper in the holes on the adapter and beveled the nuts that I used to bolt it together with (picture a lug nut and the tapered hole in a wheel rim) and it seems to have cured the problem.......I Loctited them securely of course. It was so bad that I once lost 4 bolts and damn near the t-case on the freeway before I figured out what was going on Hope that helps!---------Hans

Hans that sounds like what i am going through- i bet i would have lost some bolts eventually after seeing the one backed halfway out.

now are you saying you put studs in the xfer case? how hard was it to bevel your nuts LOL... sorry had to go there;D

no matter what i am going to replace all the hardware so i know it is clean and grime free so the locktite will work.

did installing the studs make it alot easier to install on the adapter?

 

[broncnaz]

my bolts were tight last time I checked them when I saw that it appeared to start leaking I dont remember any of them being loose. Either way I'll check mine tomorrow aslo old lock washers vcould be a issue. I want to say mine are start type lock washers as well. But I'll have to verify.

 

[Bundy]

my bolts were tight last time I checked them when I saw that it appeared to start leaking I dont remember any of them being loose. Either way I'll check mine tomorrow aslo old lock washers vcould be a issue. I want to say mine are start type lock washers as well. But I'll have to verify.

i'm not familiar with my lock washers yet, what is a start type lock washer?

 

[broncnaz]

Sorry meant star type. look like these mainly the very bottom one in the pic

 

[Bundy]

Sorry meant star type. look like these mainly the very bottom one in the pic

that's what is on there... i guess i will just get brand new ones with new bolts and locktite the shit out of it.

i have one bolt in the adapter still that won't come out (T/C side of adapter)... it looks like someone had to force it into the bolt hole. It seriously looked like a caveman used stone tools to chip at this adapter to get the bolts in some places. do you guys have this issue?

I am going to call AA and see if they made any major improvements to the newer version.

 

[broncnaz]

I've never had my tcase off since I installed it. CanT remember if any were hard to put in or not Seems like there might have been at least one that was a little tough but I truely cant tell you.. Theres not a lot of clearance around the bolts on my adapter either.
It looks like the new adapters use some studs as well as bolts. I dont remember using any studs in the transfer case side and i know that the tranny side is all bolts. I'll have to look closer. Studs might help. http://www.atlas-tc.com/pdf/50/50-2700.pdf

 

[Bundy]

i just called a tech over at AA... he didn't even know the part number i was talking about so i told him i would email a picture of the very first prototype of this adapter LOL

i may just go ahead and buy the studs that go in the tranny side- he said they still use bolts on the T/C side but that the studs have better retention.

Thanks Broncnaz!

 

[Oatmeal]

.............how hard was it to bevel your nuts LOL... sorry had to go there;D


..............did installing the studs make it alot easier to install on the adapter?

I used a hillbilly lathe to bevel the nuts........screw the nut onto a stud chucked into a drill (a drill press would be deluxe!) and hit it with a good file (or hand grinder) while it's spinning;D.......I'll bet you could find tapered nuts at a good fastener store. Why didn't I think of that?:? Yes, having studs does make it a little easier to guide the t-case onto the adapter. The real problem, though is not having the dowel pin in there to keep it from moving around. I guess if I were really energetic (I'm not) I could disassemble the t-case, bolt it to the adapter, use a transfer punch to locate a hole for the dowel from inside the empty case, drill the hole and install the dowel but........that's alot of work --------Hans

 

[Bundy]

hillbilly lathe- classic!

do you guys have this gem of a problem with the bolts being semi-permanently installed?

 

[broncnaz]

Well mine looks like its pretty close but Its not notched out. Maybe the PO used bolts that were a little longer or the mount was redesigned. I'd think that studs would help there.

 

[Bundy]

i can buy studs from AA for the tranny side which would be soooo much easier to get lined up, but for the t/c side i am screwed.

i am waiting for an email response from AA to see if they have any guidance for me.

 

[broncnaz]

Just hit up a hard ware store they should have studs that will work no reason to wait on AA. The specs are in that link I sent you.

 

[Bundy]

here is what they list- although a few things don't make sense for me

8. 2x 723701 3/8-16 NUTS
9. 2x 723704 3/8 LOCK WASHER
10 2x 723711 3/8-16 X 2" STUD
11. 2x 725004 HEX NUT 1/2"-13 NAT
12. 4x 725016 S.H.C.S. 1/2"- 13 x 1-1/2"
13. 2x 725040 1/2"-13 x 2.00 STUD

#8, what does 3/8-16 mean? Is this for the upper studs or lower?
#9 obviously goes with #8
#10 studs for #8?
#11 nuts for #13 studs
#12 i am assuming these are for the t/C side, but shouldn't it be x6? These are socket head cap screws?
#13 Why is this stud 1/2" when the #10 stud is 3/8? i don't remember them being different sizes...

 

[broncnaz]

3/8-16 is a 3/8" nut with 16 pitch threads. You'll need a stud that has the same threads. I think they are only using 2 studs probably in the locations that you have notched because there adapter is still like that. Other wise you reuse the old bolts.
I know my kit came with the socket head cap screws I still have them I didnt use them my guess in the areas that are hard to get a wrench on you could use the socket head screws. The 1/2" Stiuds are for the transmission to adapter end. So you could use studs there as well in the hard to get to spots.

 

[Bundy]

oh so they use two studs on each side? that makes sense, considering the shitty notches in the adapter and how much easier it would be to line it all up.

thanks for the help Bronconaz!