NV4500 swap is underway

[martindc1]

Originally Posted by DirtyLarry

Yes, you can use a mechanical clutch with the AA bellhousing, or add the bracket for hydraulic like I did. The bell works with both. The advantage of a hydraulic clutch is that it is easier to step on and they clutch works flawlessly even when the frame is all twisted up while off-roading.

Snip...

So with the AA bellhousing, you used the square-body master cylinder. Do you use the square-body slave cylinder? Did you use a stock clutch hose or did you go with something aftermarket? I believe I priced the stock replacement hose at around $90 which seems kind of high to me.

[DirtyLarry]

Originally Posted by martindc1

So with the AA bellhousing, you used the square-body master cylinder. Do you use the square-body slave cylinder? Did you use a stock clutch hose or did you go with something aftermarket? I believe I priced the stock replacement hose at around $90 which seems kind of high to me.

Yes, yes and yes. All were ’85-’91 square body style hydraulic clutch pieces.

NCF 72128 Clutch Master Cylinder $32.59
NCF 73117 Clutch Slave Cylinder $29.99
UP 38559 MC to Slave hose $83.88

These are Napa part numbers. I just ordered all of this stuff again the other day as I am getting ready to do a NV4500 swap in my Suburban over the Christmas break. You're right, the hose is a bit spendy for what it is.

[special-K]

Have you had chance to look at that transfer case linkage adjustment?

[DirtyLarry]

Originally Posted by special-K

Have you had chance to look at that transfer case linkage adjustment?

On the Burb? Nah, not yet. Had to put an axle shaft and lower control arm in my buddy's daughters Maxima today then play Christmas shopping with the wife so no quality time with the burb today. Maybe tomorrow I'll get a chance to peek at it. It is coming apart next weekend anyway so no biggie.

[K20chevy]

I´m running the S6 650 in my truck, a 78 K20... I think it is a great shifting tranny. Better than any other truck manual I´ve drivven before. But Larry is right, you need to pretty much cut out the whole transmision tunnel and fab a new one because this tranny is about 2 to 3" higher than the stock 4 speed...

Was it a lot of work to put it in: YES, youbet. Was it worth it? I would say so as I don´t know many 78 K20s with a 6 speed manual!

I´m happy with the swap.

And to the shift pattern: there is a reason for that. rev. and 1st are in line, so if you back up a trailer and need to go between 1st and reverse a lot you don´t have to switch the gate -> faster shifting. And mine also has a huge resistance to go into the rev./1st gate. you almost have to slam the leaver over to even get into that gate. so going into 2nd to start out is as if there was no gate to the left of it. Seems like you must have a realy early version. Mine is from an 06, so the last year they were offered.

I absolutely love mine behind the 6.2l L92.

Originally Posted by DirtyLarry

Muckmorris,

I am not running any kind of speed sensor. Just the stock speedo cable from the NP205 tcase to the speedo head.

Critter,

Nah, I never considered a ZF S6-650. I have one of those behind an 8.1L in my 2500HD and not real fond of it. It is one awkward shifting transmission. Have you ever driven one? The NV4500 is so much nicer shifting. Aside from that, I don’t think it would fit without a body lift or significant firewall and trans tunnel work. The ZF is HUGE but is probably a much stronger trans than a NV4500. I haven't heard of any ZF's with OD gear set issues or anything else that the NV4500 are famious for

[DirtyLarry]

Wow, a S6-650 behind a 6.2L must be like driving a race car engine backed by a dump truck transmission

Glad you like yours….you could have the ZF S6-650 in my 2001 2500HD. I hate the damn thing. Worst shifting manual trans I’ve ever owned with an even worse shift pattern. I’ve own that truck since new and 13 years later it has finally started to loosen up where it isn’t quite as notchy as it was up to this point (It just turned 59,000 miles last week) but I still hate it. The clutch pedal geometry on the GMT900 trucks is also quite funky. There is no slip to it, it works like an on/off switch where it is almost impossible to launch the truck smoothly. Between the clutch operation and the awkward shifting ZF 6 speed is why it has only racked up 59K in 13 years. I don’t like to drive it much.

I still prefer a NV4500 over the ZF any day, but there is no doubt about it the ZF is a much stronger transmission by a long shot.

[K20chevy]

Like I said before and someone else mentioned it before, my S6 650 (and his) shift really smooth, so you must have gotten a bad one. And I have to admit that my clutch linkage and all that is totally different anyways since I jused the duramax hydraulics with the OEM 78 clutch pedal with a home turned and welded mount. so my clutch pedal has about half the throw of the stock one. Takes a little to get used to, but makes for really fast shifts. And together with the 6.2 L92, it makes for a fun and fast combination. The ZF in my truck the way it is set up actually has relatively short throws for a truck tranny and also I think it shifts really nice. You really must have gotten a bad example.

I even think I have an on bord video from a stand still shifting through the gears..that shows how nice it does shift...

Originally Posted by DirtyLarry

Wow, a S6-650 behind a 6.2L must be like driving a race car engine backed by a dump truck transmission

Glad you like yours….you could have the ZF S6-650 in my 2001 2500HD. I hate the damn thing. Worst shifting manual trans I’ve ever owned with an even worse shift pattern. I’ve own that truck since new and 13 years later it has finally started to loosen up where it isn’t quite as notchy as it was up to this point (It just turned 59,000 miles last week) but I still hate it. The clutch pedal geometry on the GMT900 trucks is also quite funky. There is no slip to it, it works like an on/off switch where it is almost impossible to launch the truck smoothly. Between the clutch operation and the awkward shifting ZF 6 speed is why it has only racked up 59K in 13 years. I don’t like to drive it much.

I still prefer a NV4500 over the ZF any day, but there is no doubt about it the ZF is a much stronger transmission by a long shot.

[DirtyLarry]

Glad you are enjoying it. There is no doubt in my mind that transmission will probably last forever. I don’t buy into that I got a bad ZF 6 speed as I have driven several other ZF 6 speeds in GM and Ford Stupid Duties and they shift equally sucktastic, but that is just my opinion. I happened to love the way the NV5600 shift gates and pattern is laid out but there are people that hate that trans and prefer the ZF 6 speed. It’s all in what you like. I still like the NV4500 the best.

[DirtyLarry]

So it’s been almost 4 years and 10 to 15,000 miles since the NV4500 swap and last March coming back from Death Valley the NV4500 really started screaming in 5th gear. With that I knew it was time for a 5th gear cog and fresh mainshaft. Not wanting to cut another mainshaft to make the Advance Adapters kit work I started getting serious about finding a round pattern 205. Once again, birddog Mosesburb found me one with member Ryanroo so coming back from the Overland Expo in Flagstaff last May I stopped by Ryan’s place and picked it up (Mosesburb is like a bird dog….tell him what you want and he can sniff it out, anywhere anytime. He found my brand new in the box front Dana 60 and a few Warn winch bumpers for me).

So the big mystery here is why did the trans defecate 5th gear in the first place?? Well, at first I really wanted to blame the Advance Adapters kit just because I typically really hate aftermarket stuff but once my trans rebuilding friend took it apart, the AA collar that holds 5th gear was tight to my surprise. I figured the AA collar came loose and allowed 5th gear to walk around and knurled the mainshaft. The mainshaft was indeed slightly knurled and the gear did rock a bit but the collar was indeed holding it tight. With that, maybe the naysayers are right about towing in 5th gear eat up NV4500’s. I dunno, I know a few guys that tow like crazy in 5th gear and have never had a problem with them. I also don’t tow but the truck does weight 8,000 lbs. Maybe I overheated it in Death Valley and hauling balls down the mountainious Hwy 160 from AZ to I-25 in Trinidad, CO

Not sure, but this time the 205 will directly mounted to the trans with no adapters and coolers are being added to the trans just for safe measure then we’ll see how it does. If this things craps again, next go around will be something different like an Allison. That would be a tough pill for me to swallow because automatics are against my religion.

Bought this gem from Ryanroo. A round pattern 205


I didn’t get around to ripping into the round 205 until December 2013. It came to me with a slip yoke rear but I used the rear section from another 205 I had laying around with a 1350 fixed yoke. I also traded did some trading with ORD for the long 32 spline input for a short 32 spline input. This picture is just after I gutted it in preparation for sand blasting. The internals were in great shape, almost like new. I only had to replace two bearings in the whole thing.


The rear transfercase section actually came out of the 205 that was in my dad’s ’78 K20 wrecker. No wonder the speedo hasn’t worked in that truck for many years! Look at that speedo cog! The good news is you can still buy new ones from GM.


I also got a new speedo adapter for it as well. There is a seal inside the adapter that isn’t replaceable but you can get new adapters from GM also. The new adapter is not pictured here though.


With getting away from the AA kit also meant I had to find an OEM rear trans cover and modify it to clear the shift rail and idler nut. Argonaut and I were going through the mods at the same time and both of us did pretty much the same procedure to make the clearance holes.


My ain’t that purdy!


I used a wood spade to make the hole . Hey, it worked!


After making an access hole for the range shifter rail and idler shaft nut clearance


As Argonaut pointed it out the trans cover needs to be clearance to allow the 4 NP205 front seal retainer bolts to pass through. This was before I made the mod


It doesn’t take much elbow grease with a rattail file to make a pass through for the tcase front seal retainer bolts. A bit of flat filing on the seal retainer itself was also required as it appeared to be too thick to seat into the transmission cover properly.


Here tis right before I stabbed it in the truck.


Here is the trans all sinched down. One thing new is the Energy Suspension trans mount. The old AA kit trans cover bolted directly to the homemade square stock bracket.


So that is where I am at as of right now while I wait on a few parts. The drive shafts are in town being reworked as the rear is being changed to a 1350 U-joint for the tcase end and I am using a flange mount front shaft this time instead of the old yoke style mount that is a MOFO to install due to only being able to turn the bolts ¼ turn a time. The new front shaft needed to be lengthened and of course the CV needed the full-on replacement. The shafts should be done Monday and the trans coolers should be here Tuesday. That’s it for now!

Here is the old deal buttoned down to a crate ready for a new home.

[Zoomad75]

I swear, you have 205's springing up there like garden Gnomes. Good work as always.

[ryanroo]

I have a 205 population issue here to. Even though Larry decided to try and help it didnt matter. only a few months later another wayward gearcase found a home under my workbench.

Larry, you may know this already and not care, but an OEM trans W style trans cross member will bolt right up to the NV4500 mount without the need for the double stack of bushings.

As always your work is fantastic and very clean. looks great

[DirtyLarry]

Originally Posted by Zoomad75

I swear, you have 205's springing up there like garden Gnomes. Good work as always.

Hehe, seems that way Can't have too many spare parts though.

Originally Posted by ryanroo

I have a 205 population issue here to. Even though Larry decided to try and help it didnt matter. only a few months later another wayward gearcase found a home under my workbench.

Larry, you may know this already and not care, but an OEM trans W style trans cross member will bolt right up to the NV4500 mount without the need for the double stack of bushings.

As always your work is fantastic and very clean. looks great

I think all 4x4 gear heads have at least one or two tcases laying around. Mosesburb has a 205 or two laying under his bench too. Thanks for the kind words dude.

Ah...yes, you mean this crossmember like what is in my Polar Bear Burb below? Ya, I know it that xmember works great with a NV4500 but then period correct double xmember and big skid plate wouldn’t fit plus both xmembers would have to be moved back a few inches which would be an issue on a short bed. I also didn’t want to drill more holes in the already overtaxed 1/2 ton frame. For those reasons we made the cantilever bracket for the mount to mount in order to keep the stock xmembers in their original locations.




This is an OLD picture but I like this xmember and skid plate combo better than W xmember in the Burb. The W xmember sure makes the NV4500 an easy swap though!

[ryanroo]

Hmmn. that was one i hadn't seen before. i didnt realize the late 80s/early 90s trucks had different crossmembers.

this is the one i was thinking of. this is your case in its original home.



I understand about not wanting to change the current stuff. if it works why mess with it. i figured you knew about the other options but ya never know...

[DirtyLarry]

Originally Posted by ryanroo

Hmmn. that was one i hadn't seen before. i didnt realize the late 80s/early 90s trucks had different crossmembers.

this is the one i was thinking of. this is your case in its original home.

I understand about not wanting to change the current stuff. if it works why mess with it. i figured you knew about the other options but ya never know...

The xmember in the Polar Bear Burb is the original SM465/241 piece. This was the only “W” type I knew about.

Hmmm, well heck! I don’t recall seeing the one you posted before. It looks like it might work just as well, if not even better, if it mounts in the same spot as mine. Looks like the current skid plate would still work and nice clearance for exhaust too. I’ll keep my eyes open for one like that if I ever need to change it for some reason. Thanks for the heads up!

[argonaut]

Perhaps the reason for the 5th gear failure comes from high frequency vibrations present in the absence of the stock damper.

In my research I seemed to find that the Dodge units without dampers had more fifth gear failures than the Chevy units which use them. This may have been coincidental, but the engineers decided to use the dampers for a reason and so it was a one of the reasons that I decided to retain the stock damper and adapter just like Larry is showing here.

Larry are you at all concerned that the NP205 weighs almost twice as much as the 208 or 241 that was intended to hang off of that adapter?

[K20chevy]

Out of my own experience with an aluminum tail housing braking off dumping the t-case on the interstate, I can just advice everyone to run a second crossmember, second tranny mount and an adapter like I have used on my truck. Works perfect and gives you the extra insurence in case something does let go, that the t-case will stay unter the truck.

here are the pics...

mock up:



final install:



final install close up:



2nd cross member from the side:

[DirtyLarry]

Originally Posted by argonaut

Perhaps the reason for the 5th gear failure comes from high frequency vibrations present in the absence of the stock damper.

In my research I seemed to find that the Dodge units without dampers had more fifth gear failures than the Chevy units which use them. This may have been coincidental, but the engineers decided to use the dampers for a reason and so it was a one of the reasons that I decided to retain the stock damper and adapter just like Larry is showing here.

Larry are you at all concerned that the NP205 weighs almost twice as much as the 208 or 241 that was intended to hang off of that adapter?

I often wonder about the damper too. GM applications didn’t use dampers behind gas engines, only 6.5L diesels to dampen the pulses of the rattley diesel. Sometimes I also wonder if the way I lug the truck does more damage than just conserving fuel. The 8.1L has plenty of torque where I am often already in 5th before going 40 – 45 MPH.

No, I am not worried about the weight of the 205 on the aluminum adapter/rear trans cover at all but maybe I should be?? To me, the NV4500 aluminum adapter even looks sturdier than the old school 465/205 adapters that were known for cracking. Now with that said, had I used a 205/203 doubler like others have done I definitely would have gone with a cast iron adapter. Seems all the cast iron adapters are for the Dodge version of the NV4500 instead of GM. Maybe I am wrong or just didn’t look hard enough. What are you planning to do with yours? I certainly do not recommend using the 205 side bracket to bolt it to the frame!

[ryanroo]

ive had my 205 hung off the back of the GM 4500 tail housing in my jeep for the last 4-5 years. no issues at all. granted it doesn't see a lot of miles, but i have beat and bounced it pretty hard on a few occasions. i even have the AA spacer to amplify the situation. cast aluminum doesnt stretch, or bounce much, so unless the mating of the two is loose, it would have little room for movement that would lead to cracks. i also have a big block in mine and drive in 5th almost all the time on the road. my 4500 came behind a 350 originally and has no damper. it had 125k on it when i pulled it and all i did was an inspection and stuck it back together. anyhow, i haven't yet had any 5th gear issues. ill hope that remains the case.

[Dieselwrencher]

Larry, that 205 looks pretty dang nice. Most of the 5th gear issues we see are on pre 98 dodge NV4500's that aren't upgraded at all, and on the 98 later ones, people having double or triple the power and driving like sports cars. I agree, I believe lugging is what takes most of them out. We've had a couple with upgraded nuts and main shafts still have issues. They were stock VP trucks. Another new nut and some performance upgrades and they have been fine. They tow in 5th all the time and it's been over 2 years now. The new 5th gear fix is the best way to fix it but kind of costly. My brother put one in his 92 F-350 after the nut backed off it on the way to Ca a while back. I was surprised it came off but that truck was used as a pulling truck the whole summer before.

On the weight hanging off the aluminum tail housings, yeah, we've seen a couple of first gen NV4500 swaps that had an early failure from the tail housing being cracked and the trans gear lube leaking out and the trans being ran out of oil until it's dead. We switch over to a cast tail housing on all of them we do just for peace of mind. That second mount is a good idea too.

[argonaut]

My plan all along has been to add a simple steel brace that sits above the tail housing and bolts to the upper two locations on the transmission and the upper three locations on the transfer case. It's a little hard to explain and I haven't yet sketched up a design. Just a couple ideas floating in mind. The point is that the top of the tail housing is in tension from the moment about the mounting points caused by the gravity force on the transfer case. My steel brace would allow the tension forces to be transmitted through it, in addition to the aluminum housing, directly from the t-case to the back of the trans. Unfortunately this does nothing to absorb the shear forces, but perhaps that could be mitigated if the brace also tied down to the tail housing mount locations. I'll need to think about it a little more before I start fabricating.

Or maybe the additional rear mount would be easier

[ryanroo]

My thoughts when i built the jeep, were to take off from the rear output housing mounting bolts. then i could hang the case from the top and it wouldnt be as much of a pain to drop it. i still wouldnt mind doing it, as it sits now the belly pan also supports the trans and transfer. it makes it a bit of a chore to pull the belly pan. i would much rather have the gearboxes hung from the top so the skidplate can be removed without as much hassle.

i wasn't terribly worried about it causing fatigue issues so i never pursued the second mount and i had some clearance issues for fabricating the top mount which have since been relieved by some roll cage tubing.

[arrover]

I don't know all the ins and outs of NV4500/205 setups since I don't have that in my truck BUT, I thought I should post this just in case you guys hadn't seen it: http://diy4x.com/cart/index.php?rout...product_id=202 . Maybe it helps, maybe it doesn't. Great thread though. Thanks for all of the info!

[DirtyLarry]

Well, I am not going to worry about an added support for the 205. There are lots of people running this combo just like I have it with great success. Maybe it if was a full on rock crawler or something crazy it would be more important. Hell, I’ve got a nice big skid plate to catch it if it falls off!

Alas she’s all bolted together again! All I have left is to install are the new shift knobs coming from JB Fabrication which should be here Friday. One of the ORD shift knobs broke when I tightened it too tight, glad it broke too as the JB knobs have the shifter map engraved in them. I haven’t had a chance to go for a test drive yet as the batteries were dead (poor truck hasn’t left the house since last June)....maybe Friday I'll be able to take it for a spin.

Picked up $475 worth of driveshaft’s Monday. The rear needed a new stub and slip yoke to accommodate the change to the larger 1350 u-joint at the tcase. I’ve had a 1350 at the rear axle for quite a while but the tcase end was really small, like a 1210 or something. The front shaft needed the works…CV rebuild, new joints, the stub and yoke were loose so they got replaced and it needed to be lengthened almost 2”. All the U-joints are the Super Brute solid core cross shafts.


Beefy. It’s an optical illusion where the ebrake cable looks like it is near the yoke when it is actually a few inches away from it.


I spent a lot more time this go around fine tuning the ORD twin stick adjustment. I really like the way it shifts now. Having front wheel drive seems really weird to shift only that stick. BTW….to run only in front wheel drive the rear shifter must be left in neutral, which is nice so you don’t end up running the front and rear in two different range speeds.


The trans coolers are HUGE! The coolers also add 2 quarts of capacity. Either they are going to help keep the fluid cooler or help keep it really hot from the heat of the exhaust Time will tell! The picture also makes it look like the front shaft is uncomfortably close to the trans cooler but there is plenty of room. The Dana 60 will have to crash through the 8.1L oil pan before the shaft hits the cooler.










Now that all this is done I’ve still got a ton of work to do to it before the next big desert trip coming up in May. The rear winch needs work (again) because it stopped working (again). This damn Milemarker winch is broke more than it actually works. Junk!

Then I need to get it up to Denver to spend a week with Phoenix as they are going to remodel the kitchen area to the latest and greatest stove/sink combo instead of the old fashion rattle trap camp stove that is in it now. It is also getting fitted with 100W solar power.

Lastly, I may still have an issue with the rear axle to figure out. Last spring on the Death Valley trip it puked out over a quart of 80W-90. When I got home I changed the rear cover to add capacity then filled it with Synthetic thinking it just overheated. A couple months later I drove it to Arizona for the Overland Expo and the sumbish puked out another quart of oil out the vent on that trip. Talk about a friggen mess all over the rear of the truck and camper when it decides to have its gear oil orgasm. I’ve since replaced the vent hose and installed a new vent so the trip to Denver should be a good test for that. I just don’t know what would cause this thing to start puking out oil out of the blue. There is zero noise coming from the axle that would point towards any bearing issues.

[Redcap]

Originally Posted by DirtyLarry

Well, I am not going to worry about an added support for the 205. There are lots of people running this combo just like I have it with great success. Maybe it if was a full on rock crawler or something crazy it would be more important. Hell, I’ve got a nice big skid plate to catch it if it falls off!

Alas she’s all bolted together again! All I have left is to install are the new shift knobs coming from JB Fabrication which should be here Friday. One of the ORD shift knobs broke when I tightened it too tight, glad it broke too as the JB knobs have the shifter map engraved in them. I haven’t had a chance to go for a test drive yet as the batteries were dead (poor truck hasn’t left the house since last June)....maybe Friday I'll be able to take it for a spin.

Picked up $475 worth of driveshaft’s Monday. The rear needed a new stub and slip yoke to accommodate the change to the larger 1350 u-joint at the tcase. I’ve had a 1350 at the rear axle for quite a while but the tcase end was really small, like a 1210 or something. The front shaft needed the works…CV rebuild, new joints, the stub and yoke were loose so they got replaced and it needed to be lengthened almost 2”. All the U-joints are the Super Brute solid core cross shafts.


Beefy. It’s an optical illusion where the ebrake cable looks like it is near the yoke when it is actually a few inches away from it.


I spent a lot more time this go around fine tuning the ORD twin stick adjustment. I really like the way it shifts now. Having front wheel drive seems really weird to shift only that stick. BTW….to run only in front wheel drive the rear shifter must be left in neutral, which is nice so you don’t end up running the front and rear in two different range speeds.


The trans coolers are HUGE! The coolers also add 2 quarts of capacity. Either they are going to help keep the fluid cooler or help keep it really hot from the heat of the exhaust Time will tell! The picture also makes it look like the front shaft is uncomfortably close to the trans cooler but there is plenty of room. The Dana 60 will have to crash through the 8.1L oil pan before the shaft hits the cooler.










Now that all this is done I’ve still got a ton of work to do to it before the next big desert trip coming up in May. The rear winch needs work (again) because it stopped working (again). This damn Milemarker winch is broke more than it actually works. Junk!

Then I need to get it up to Denver to spend a week with Phoenix as they are going to remodel the kitchen area to the latest and greatest stove/sink combo instead of the old fashion rattle trap camp stove that is in it now. It is also getting fitted with 100W solar power.

Lastly, I may still have an issue with the rear axle to figure out. Last spring on the Death Valley trip it puked out over a quart of 80W-90. When I got home I changed the rear cover to add capacity then filled it with Synthetic thinking it just overheated. A couple months later I drove it to Arizona for the Overland Expo and the sumbish puked out another quart of oil out the vent on that trip. Talk about a friggen mess all over the rear of the truck and camper when it decides to have its gear oil orgasm. I’ve since replaced the vent hose and installed a new vent so the trip to Denver should be a good test for that. I just don’t know what would cause this thing to start puking out oil out of the blue. There is zero noise coming from the axle that would point towards any bearing issues.

I am envious of that awesome setup, DirtyLarry!

[vectorit]

Originally Posted by Redcap

I am envious of that awesome setup, DirtyLarry!

Me too!

Excellent work