'91 K5 Four Wheel Camper

[Capt Ron]

Ok, I have not seen any time lines mentioned, no 5.3s posted for sale.... Once again, it is hard to play follow the leader when the leader keeps stopping to tie his shoe!

 

[deadman]

I'm quite interested to see how you get this hooked up to the blazer clutch pedal assembly...master cylinder/line/etc..

 

[campfire]

98 housing. Internal throwout bearing. As in, no clutch fork.

I like the serviceability of external slaves, but internal slaves avoid all the potential clearance issues.

 

[campfire]

I'm quite interested to see how you get this hooked up to the blazer clutch pedal assembly...master cylinder/line/etc..

@ZooMad75, a quick check of Rockauto indicates that a '98 NV4500 uses the same clutch slave as a '99 4.8L NV3500 (which is what I have in my suburban). Based on that, if I were in your shoes, I would buy a slave cylinder from a 2005 GTO. Same mount, same bore, same stroke. But it uses a normal M10 bubble flare fitting instead of the awkward click-type connector that most of GM's slaves used in that era. I bought a standard square body M/C, a standard square body clutch hose, and one adapter to connect the stock M12 fitting to the M10 fitting on the slave. Easy-peasy, since you're going the internal slave route.

There are pictures buried in the burb thread (sometime this past spring/summer)

 

[deadman]

Nice info @campfire

 

[ZooMad75]

Ok, I have not seen any time lines mentioned, no 5.3s posted for sale.... Once again, it is hard to play follow the leader when the leader keeps stopping to tie his shoe!

Well, I may not have to post a for sale ad on the 5.3. I've got a customer at work that has a Jeep YJ rock crawler project with a 700r4 and was intending on using a 6.0 out of a Denali he bought on the cheap. He flipped it instead of pulling the engine. So he's in need of a 5.3 or 6.0. When I told him what I'm up to with mine on his last service visit (JKU Wrangler Rubicon with $20 grand worth of Dana Crate 60's under it) he said to call him first when I'm ready to pull mine out. He'd take the engine/trans/controller/harness as it is and stuff it into the YJ. As I found from the dough he stuffed into his JKU between the axles, lift and other goodies he's not afraid of spending money. I'll give him first shot at it.

As far as timeline goes, it really comes down to having the parts in hand. Some prep needs to happen on the engine, seal up, clean up and paint. But I need the trans, clutch and a few other things to be ready to pull the drivetrain out. Larry and I would like to get the swap together and do it over a couple of weekends with him putting some midnight oil in when he is able to. Neither of us want to incapacitate the truck until we know we can turn and burn to get it back on the road again. He's got stuff he needs to do on his junk too so I have to move when he's got shop space available for me. Ideally, I'd have it ready to go before summer, but really it's going to come down to the money and time variables.

I'm quite interested to see how you get this hooked up to the blazer clutch pedal assembly...master cylinder/line/etc..

Larry's done some checking on this and thinks he has a recipe that will marry the GMT400 truck hydro throwout with the squarebody clutch master. @campfire 's combo of the GTO bearing with the squarebody master is an option we will explore.

I like the serviceability of external slaves, but internal slaves avoid all the potential clearance issues.

After looking at the 98 setup from the donor truck it's just a cleaner setup. Plus it eliminates the possibility for machining errors or mismatch in the fork to pivot to bearing combinations. You can dig back through a few threads here where people had to deal with a different combo of throwout bearings to forks. Larry brings up a valid point between both his Burb and the K10. If you looked at the parts list between the two, they were identicle to start with. Same AA bellhousing, stock replacement squarebody master/slave, clutch fork, throwout bearing and clutch. The Suburban has never felt as good as the K10. One issue was glaring to start, the pushrod from the slave to the fork needed almost an extra inch added to get the right throw on the fork. That's over what the K10 had for sure. Adjustment has been super touchy due to the added length (we think) and even after changing the clutch to a fresh centerforce, re-bushing the clutch pedal and replacing the broken return spring on the pedal the feel still wasn't the same as the K10. It's after we've gone over the details multiple times we think the problem might be in the AA bellhousing. As in the pivot mount may not be in the same spot as it is on the K10's AA bellhousing. Granted the difference in feel is minor, but it's the inconsistency that is bugging Larry. It's that BS we are trying to avoid here. A straight hydraulic throwout bearing eliminates the fork, pivot and stock bearing and possible mismatch thereof.

@ZooMad75, a quick check of Rockauto indicates that a '98 NV4500 uses the same clutch slave as a '99 4.8L NV3500 (which is what I have in my suburban). Based on that, if I were in your shoes, I would buy a slave cylinder from a 2005 GTO. Same mount, same bore, same stroke. But it uses a normal M10 bubble flare fitting instead of the awkward click-type connector that most of GM's slaves used in that era. I bought a standard square body M/C, a standard square body clutch hose, and one adapter to connect the stock M12 fitting to the M10 fitting on the slave. Easy-peasy, since you're going the internal slave route.

There are pictures buried in the burb thread (sometime this past spring/summer)

I'll go back and re-read that on your burb thread. It may be along the same lines as what Larry's been thinking, but it's smart info I'll check out. Thanks!

 

[campfire]

Plus it eliminates the possibility for machining errors or mismatch in the fork to pivot to bearing combinations. You can dig back through a few threads here where people had to deal with a different combo of throwout bearings to forks. Larry brings up a valid point between both his Burb and the K10. If you looked at the parts list between the two, they were identicle to start with. Same AA bellhousing, stock replacement squarebody master/slave, clutch fork, throwout bearing and clutch. The Suburban has never felt as good as the K10. One issue was glaring to start, the pushrod from the slave to the fork needed almost an extra inch added to get the right throw on the fork. That's over what the K10 had for sure. Adjustment has been super touchy due to the added length (we think) and even after changing the clutch to a fresh centerforce, re-bushing the clutch pedal and replacing the broken return spring on the pedal the feel still wasn't the same as the K10. It's after we've gone over the details multiple times we think the problem might be in the AA bellhousing. As in the pivot mount may not be in the same spot as it is on the K10's AA bellhousing. Granted the difference in feel is minor, but it's the inconsistency that is bugging Larry. It's that BS we are trying to avoid here. A straight hydraulic throwout bearing eliminates the fork, pivot and stock bearing and possible mismatch thereof.

Yeah. As much as I enjoyed the ease of replacing the external slave on my Blazer's NV4500 (it seized up shortly after that whole swamp episode ), the linkage was completely unusable in stock form. I added 3/4" to the pushrod to get it into a useable range. Brand new slave, arm, and T.O.B., but they obviously weren't a matching set. It didn't bother me once I got it figured out, but it did wind up being a bigger initial headache than the GTO slave in the 'burb.

@Larry, did you maybe have differently adjusted pivot studs?

 

[campfire]

Larry's done some checking on this and thinks he has a recipe that will marry the GMT400 truck hydro throwout with the squarebody clutch master. @campfire 's combo of the GTO bearing with the squarebody master is an option we will explore.

I'll go back and re-read that on your burb thread. It may be along the same lines as what Larry's been thinking, but it's smart info I'll check out. Thanks!

Yer welcome! There are a bunch of ways to skin this cat. It helps that so many drivetrain combinations have compatible master/slave geometries. You can pick from a range of masters and slaves and it's just a matter of adapting the hydraulic line.

 

[ZooMad75]

@Larry, did you maybe have differently adjusted pivot studs?

I think as far as Larry's stuff was, he used the same pivot. He's got every part number saved and as the theory would be if he used the same parts he'd get the same results. This is not the case. But until he needs to pull the trans again for something he's not going to push to go after it. We might need a measurement of @Capt Ron 's AA bellhousing to have a comparison point to see if they did indeed make a change in the pivot ball location and not say anything.

 

[campfire]

I think as far as Larry's stuff was, he used the same pivot. He's got every part number saved and as the theory would be if he used the same parts he'd get the same results. This is not the case. But until he needs to pull the trans again for something he's not going to push to go after it. We might need a measurement of @Capt Ron 's AA bellhousing to have a comparison point to see if they did indeed make a change in the pivot ball location and not say anything.

Is the height of the ball adjustable?

 

[ZooMad75]

Yer welcome! There are a bunch of ways to skin this cat. It helps that so many drivetrain combinations have compatible master/slave geometries. You can pick from a range of masters and slaves and it's just a matter of adapting the hydraulic line.

That's the idea. It fits the goal of keeping it simple.

 

[Capt Ron]

We might need a measurement of @Capt Ron 's AA bellhousing to have a comparison point to see if they did indeed make a change in the pivot ball location and not say anything.

I actually have 2 different AA bellhousings and although they both have the same casting # {712548} they are machined differently. One is definitely for the early 4500 part #712577 and from my research I think the other one is part #712576 {no stamped # so not sure} is for the later GM 4500 and the Dodge 4500. I would assume the ball adjustment casting area is theoretically supposed to be the same although there could be different tolerances from the machining process. I will post up some detailed pics for all to see tomorrow.

 

[ZooMad75]

I actually have 2 different AA bellhousings and although they both have the same casting # {712548} they are machined differently. One is definitely for the early 4500 part #712577 and from my research I think the other one is part #712576 {no stamped # so not sure} is for the later GM 4500 and the Dodge 4500. I would assume the ball adjustment casting area is theoretically supposed to be the same although there could be different tolerances from the machining process. I will post up some detailed pics for all to see tomorrow.

That's the concern is that they have one casting getting machined differently. All the more reason to avoid the AA stuff and stick with what the General engineered originally.

 

[campfire]

I actually have 2 different AA bellhousings and although they both have the same casting # {712548} they are machined differently. One is definitely for the early 4500 part #712577 and from my research I think the other one is part #712576 {no stamped # so not sure} is for the later GM 4500 and the Dodge 4500. I would assume the ball adjustment casting area is theoretically supposed to be the same although there could be different tolerances from the machining process. I will post up some detailed pics for all to see tomorrow.

A later bell housing wouldn't have a pivot ball or a hole in the side, and it would have a cutaway where the slave fits against the input retainer. So they should be significantly different. I guess you could do those mods in the machining phase, but that's definitely not how GM did it. Granted, GM sold a whole lot more bell housings than AA ever could. They'd have a lot bigger tooling budget to do things correctly.

 

[ZooMad75]

A later bell housing wouldn't have a pivot ball or a hole in the side, and it would have a cutaway where the slave fits against the input retainer. So they should be significantly different. I guess you could do those mods in the machining phase, but that's definitely not how GM did it. Granted, GM sold a whole lot more bell housings than AA ever could. They'd have a lot bigger tooling budget to do things correctly.

Looking at the AA website, the early and late style they sell both use a fork from the driver's side. Really the main difference is between the two kits is the later version replaces the stock input bearing retainer to the early style to allow the use of the fork/to arrangement vs the stock late style hydraulic bearing.

The pivot ball is not adjustable. But I'm sure there is more than one version that could be used. AA has thier own part number for the ball in the kit.

This discussion will help when Larry goes to address the issue on the burb but I've set my mind to not go AA in my case. Stock engineering for me.

 

[Capt Ron]

Both ball studs measure .905 from the inside mounting surface to the tip of the ball.

 

[Kay86K5]

As far as I know, the swaglok adapter I used to connect my 95 hydro line to my 89 hydro master cylinder line will work on the internal slave's hydro lines too. The adapter cost me $5 and it took me 10 minutes to get installed...just FYI really

 

[ZooMad75]

As far as I know, the swaglok adapter I used to connect my 95 hydro line to my 89 hydro master cylinder line will work on the internal slave's hydro lines too. The adapter cost me $5 and it took me 10 minutes to get installed...just FYI really

I think that's the way Larry was looking. I like the GTO idea, but looking at the price the GTO slave twice as much as the stock one. That's even with me getting it at trade price.

 

[Kay86K5]

I think that's the way Larry was looking. I like the GTO idea, but looking at the price the GTO slave twice as much as the stock one. That's even with me getting it at trade price.

My little swagloc tube adapter has worked great and the clutch feels great...at least to my standards. And it was so cheap and easy, it kind of puzzles me why people go other routes that cost so much money .

To each their own though

 

[ZooMad75]

My swagloc adapter has worked great and the clutch feels great...at least to my standards. And it was so cheap and easy, it kind of puzzles me why people go other routes that cost so much money .

To each their own though

It's not a bad way to go the AA route. But I will admit they have a top notch marketing team that has them set up in many ways when looking into this swap as the only way to go. Any web search for nv4500 swap info yields them in the results. Reading thier info shows that according to them, swapping one of these transmissions into an earlier gm truck requires their setup. Looking at the late style bell housing they sell they put the early style bearing retainer on to allow the use of a standard clutch fork and throwout bearing. Which would be needed if you didn't go with a hydraulic clutch and stayed mechanical.

I'm pretty cheap too, so paying the premium on the AA engineering wasn't something I was looking forward to do.