Updated Advance Adapters NV4500 to 3 SPD Transfer Case Info (1 Viewer)

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So I decided to finally replace the factory 3 Spd transmission in my '73 FJ40 and decided on the GM 4WD NV4500. I already have a 350 Chevy that has been in the car for years. I was supposed to have the part shipped from Advance Adapters on July 1, having ordered it from Summit Racing on June 16th. To make a long story short, Advance Adapters was in the middle of a product update and I just got my parts yesterday.

It seems that they decided to change the casting from the old P/N 51-0214 which was 5.875" long to P/N 51-0224 which is now 1/2" longer at 6.375" long, same as used with the Dodge version of the transmission.

So today I decide to do the install. The documentation calls for cutting off the output shaft of the transmission at 4.498" with no plus or minus information given. When I took my initial measurement it appeared as if the measurement was right at the edge of where the splines start. I was uncomfortable with cutting right up against the splines so I eyeballed close but not on.

Here is what it looked like before the cut.

This is what is looked like after the cut.

Now the pipe wrenches and clamps in the background of the picture are what I used to remove the 5th gear retaining nut.

I actually had to put the clamp over the output shaft because when I applied pressure the whole assembly tried to twist up and off the pallet it was setting on, despite the 3/4" plywood support the bell-housing was bolted to.

Now the limited install instruction give you several options to cut the tail shaft. I decided to try a portable band saw. I wasn't sure if the blade was up to the task since it came from HF but figured the first few seconds would tell the story. To my delight, it was up to the task.

I dressed up the saw cut marks with a flapper wheel before test fitting the spud shaft.

(to be continued)

 

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So after cleaning off the old gasket sealer from the transmission housing I put the new adapter housing in place and assembled the spud shaft pieces. There were no instructions for the spud shaft assembly so I pressed the bearing into the adapter ring until the C-clip made contact. I then flipped the assembly and pressed in the spud shaft until it made contact with the bearing.

After dropping the spud shaft assembly onto the output shaft of the transmission I found that it went on without a hitch.

My only concern at this point was how much clearance was there between the new spud shaft and output shaft of the transmission. I removed the spud shaft assembly, put some Play-Doh on the end of the output shaft and then put the spud shaft assembly back in place. This is the clearance I found.

The higher portion of the Play-Doh actually fit into a recess on the inside middle of the shaft and the narrower part is the clearance between the end of the output shaft and inside of the spud shaft.

Since this is a new configuration of the package as of this month, July 2014, I'm concerned and decide to call Advance Adapters and speak with someone about my results. The person I spoke with didn't seem concerned about the cut-off length of the output shaft, only that they don't want you cutting into the splined area. The other concern was they didn't want the output shaft applying pressure to the spud shaft bearing and with nearly 1/4" of clearance I was golden. When I asked about pressing the spud shaft up against the bearing and questioned him about the possibility of the shaft now being too long protruding into the transfer case he said everything was good it would not be too long.

So this is as far as I got before the heat drove me inside for the day.

My reason for creating this thread was to inform those looking into this kit (50-0511) that it is now 1/2" longer than the previous version. The case and spud shaft were lengthened by 1/2" as part of the update. Their documentation hasn't been updated on their web site yet and the documentation provided with the updated kit was simply number changes on the old drawing on case length and casting numbers change notes.

One of the things I noted was that the factory, actually cast iron replacement, 4 WD tail housing was positioned with roll pins. The new adapter according to Advance Adapters is centered on the spud shaft rotating freely. Once things were loosely together I noted that there was a few degrees of rotation the adapter could move so on final assembly I'll try and align the adapter cross member mounting surface with the top plate mounting surface to keep things as straight as possible. It may not be much angle wise and I'm sure there will be no movement once everything is tightened, this is just me being anal and wanting things aligned perfectly if possible.

 

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So I am about to seal up the case and trying to figure out how to square up the adapter with the trans. See, up to this point I read this in the instructions:

"3. The alignment between the new adapter plate and transfer case must be performed by the new bearing that has been included with the adapter. This sealed bearing will have the external snap ring on the outside of the adapter similar to the original transmission. This will prevent the special transmission fluid of the New Venture gear box from mixing with the transfer case fluids."

I took it to mean that you didn't use the two alignment dowel roll pins that aligned the factory tail housing. Without them in place the housing could rotate a few degrees and this is what I worried about might cause a miss alignment for the trans mount; especially when you carried the distance out to the frame rails.

So I was looking for shim material that I might use around the bolts to help limit this movement. When I measured the holes in the adapter I realized that the two that lined up with the factory alignment pins were larger than the rest (.530" vs .437"). Damn, I couldn't believe it. I put the alignment roll pins in place and put the adapter over them and again I was pleasantly surprised.

The spud shaft was in alignment too. I don't know if this is a change from the previous version (prior to July 2014) or simply an oversight in the instructions. The reason being is that with the alignment roll pins in place there is no way to move the adapter housing to change the alignment of the bearing and spud shaft.

So, now it is time to determine the torque to use on the 4 Allen screws that secure the "Set Collar" before cleaning everything for final assembly. Besides not listing a torque for them there is also no mention in the instructions of using red Loctite on them but I am to ensure they don't come loose. Should they come loose I'll probably lose 5th gear which will be my sign to stop driving it before one of the screws get wedged into the gears and grenade the trans.

 

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So I located a torque value for 1/4"-28 Grade 8 bolts. Since I was using Red Loctite I went with the "wet" value of 10 lb.ft. or 120 lb.in.. Regarding the adapter mounting bolts I was using Blue Loctite on the 6 lower bolts (as they do not enter the inner cavity of the transmission) and Permatex Ultra Black Gasket Maker on the upper two (as they do enter the inner cavity) .

First is was apply Gasket Maker to the adapter.

Then put it in place.

(to be continued)

 

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Last but not least, torque the bolts to 40 lb.ft., which Advance Adapters did state in the instructions.

I double checked the spud shaft was free and clear during the process and it was. The only thing left is to get the old setup out of the car and get this installed. I do have to buy a few small parts so it won't be for a few weeks to a month at the earliest.

I hope this helps others who might be considering the same conversion.

 

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Well today I was finally able to test fit the transmission and transfer case.

Based on what I'm seeing it looks like I'm not going to have to relocate the rear cross member.

The old dual exhaust is going to have to be replaced. For one it is really rusty but there was also an H-pipe running where the transfer case now sits. The parking brake is also way to close to the exhaust hanger on the passenger side. Engine was installed back around '85-'86 using Downey parts and instructions.

 

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So I put the transmission cover in place today and it doesn't look like the NV4500 is off very far from the original 3 speed location with regard to the shifters.

A little further to the rear but nothing I can't live with.

 

[roma042987]

cool thanks for posting

 

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So today I finally bolted up the trans and transfer case for the last time, I hope.

I had to make 1/4" spacers for the rear support as they now mount just in front of the welded in tube frame cross member where the frame is wider. Parking brake and speedometer cables both reached with a little rerouting. The parking brake drum just clears the cross member by maybe 1/4". Just need to measure for the drive shaft length and have the shafts fitted. After putting in new motor mounts I'll finish the mods to the trans cover.

It would have been easier if the adapter was 1/2" shorter as the original was but it also allowed me to bolt the rear support members to the frame. If it was that 1/2" shorter I would have had to fabricate a plate to cover the factory access holes in the frame in order to bolt the mounts to the frame. As it was I did fab a 2" wide 1/4" thick plate with the two nuts for the mounts welded to it. I actually threaded the plate and then screwed the bolts through before screwing down the nuts and then welding them. This way I just had to drill the holes in the frame, insert the plate with nuts already welded to it, put a 1/4" spacer behind the mount and then simply run the bolts in. This added a full 2" X 4" frame sandwich for the mounts.