Project “Polar Bear”: 1989 V2500 Suburban
- Thread starter Larry
- Start date
Larry
Bigassgas Explorer
You guys better knock it off before I post up pictures of Zoo’s K5 with a broken axle stub and Don’s Waggy with a slashed front tire being changed by a paraplegic while Don just stands there scratching is ********
Larry that is some awesome flex you got going in your truck, and you say that the suspension flexes even more now! Holy Moly! It really gives you an idea of how rubber like the frames are on our trucks. Thanks for posting those pics. Cheers, Chilli...
Right, our old open channel framed trucks are like Gummy worms! At least now most of the flex is actually in the suspension and not all in the frame. LOL
BTW, this new forum format SUCKS! Just thought I would mention that
bknudtsen
Expedition Leader
You guys better knock it off before I post up pictures of Zoo’s K5 with a broken axle stub and Don’s Waggy with a slashed front tire being changed by a paraplegic while Don just stands there scratching is ********
Right, our old open channel framed trucks are like Gummy worms! At least now most of the flex is actually in the suspension and not all in the frame. LOL
BTW, this new forum format SUCKS! Just thought I would mention that
Not a fan of the format either. But, I am old and resistant to change...
Larry
Bigassgas Explorer
It looks like it has been about 5 years since I’ve updated anything on the ole Polar Bear Suburban so today is as good as any for an update as there are a few things worthy of posting.
For starters, the ole bear has had a pretty nasty driveline vibration for many years that I whittled at for what seemed like forever. The vibration was a high frequency vibration that pointed to driveline. Back during the Rona lockdown in 2020 I had plenty of time to play with it. After doing a lot of measurements I found the NP241 output shaft had a ton of runout, which made sense as it was wiping the tailshaft bushing and rear seal about every year so ripped it down and did a Slip Yoke Eliminator. The driveline angles had to be adjusted again once the new longer shaft was made as well.
While that made a noticeable change in the vibration it still wasn’t enough to make me happy but life and other projects got in front of it (mainly the K10 breaking in half and needing a major frame job) where I finally got around to getting back on it this summer. Along with a vibration, the bear has had a terrible feeling clutch pedal pretty much since day one when I got it but back then with the TBI 350, the issue was just a flat pressure plate then I replaced that with a used leftover Centerforce from the K10 when I did the NV4500 swap around 2012 using an Advanced Adapters bellhousing. Then in 2015 when the bear got its 8.1 swap I started with fresh hydraulics and a new Centerforce clutch and had the flywheel turned at our local driveline shop. After that swap was complete the bear had a ton of new power but the less than sterling clutch woes continued although they issue felt different.
I dealt with the poor clutch issue for years where it just felt like the release bearing wasn’t pushing the pressure plate far enough. It launched with a lot of chatter and grabbing reverse was near impossible without turning the engine off. Given how inconsistent Advanced Adapters quality is, I suspected the clutch fork pivot ball was in the wrong location, wrong ball or whatever so I decided to pull the AA bell and use a factory GM bell from a 1996+ with internal slave/release bearing, which also required a new clutch and PP. Being on a budget I chose to go with a run of the mill LUK clutch, which worked okay but wasn’t nearly a good performer as the Centerforce. Those changes did make a slight difference but still not enough to make the pedal feel nearly as good as the K10.
Fast forward to this past June, I decided to get a new Centerforce clutch kit for a 1996+ 454 but this time I decided to get a fresh flywheel since that is about the only thing I haven’t changed throughout all of the clutch issues that came to be after the 8.1 swap. As I pulled the old flywheel out and laid it next to the new flywheel it was a complete “AH, HA!” moment when I saw what the driveline shop did 7 years ago. Those clowns completely machined off the lip where the pressure plate rides. The amount of metal they took off was thicker than a quarter and certainly would make a difference in the dept of the release bearing push. The flywheel balancing holes are also on that same outer plane where they wiped those down too!
Long story short, the new flywheel fixed the clutch engagement issue AND the vibration issue that’s been driving me crazy for all these years…….and the Centerforce clutch allows the NV4500 to shift as close to a sports car as one could get. I totally didn't expect this flywheel to fix the vibration as the vibration felt more speed related than RPM related but then again I don't drive these 8.1s at 2500+ RPM at a constant pace in any other gear than 5th. So, for you 8.1L guys with manual transmissions be careful if you ever have your flywheel turned. Probably better off just replacing the flywheel rather than having it turned. Shame on me for not noticing the day I picked up the flywheel from the driveline shop back then.
Lip vs no lip
Centerforce on left and LUK on right
Centerforce on left and LUK on right
So, with that success I fell back in love with the ole bear and decided it needed more love so it inherited a hand me down old school Hickey Sidewinder winch that came off my K10 a few years ago, which was a hand me down from my dad's buddy that bought this winch brand new as a dealer installed option on his 1978 K20 way back in the day. It was quite the time consuming blacksmithing project reworking the brackets and skid plate designed for a 73-80 to fit an 81+ with much different frame horns and bumper shapes. Funny, these old winches used tiny 7/16 cable that was only about 2 feet long This time it got treated to 85 ft of 3/8 synthetic rope. I really didn't think a full 100 ft would fit on the spool. I'm still deciding on a hook though..thinking of a Warn Epic Sidewinder, a Factor55 dealeo like the one on the K10 or stay with nothing at all as it is now.
When the Sidewinder was on the K10
I restored an old period correct Warn bumper with a Warn 12k to replace the Sidewinder
Now it lives on the Polar Bear
I made some snazzy bump stops so the plate wouldn’t get pushed into the bumper driving on the highway
Solenoid packs
Winch neutral pull rod
100% Jeff Bezos Chinesium winch rope
Continued............
For starters, the ole bear has had a pretty nasty driveline vibration for many years that I whittled at for what seemed like forever. The vibration was a high frequency vibration that pointed to driveline. Back during the Rona lockdown in 2020 I had plenty of time to play with it. After doing a lot of measurements I found the NP241 output shaft had a ton of runout, which made sense as it was wiping the tailshaft bushing and rear seal about every year so ripped it down and did a Slip Yoke Eliminator. The driveline angles had to be adjusted again once the new longer shaft was made as well.
While that made a noticeable change in the vibration it still wasn’t enough to make me happy but life and other projects got in front of it (mainly the K10 breaking in half and needing a major frame job) where I finally got around to getting back on it this summer. Along with a vibration, the bear has had a terrible feeling clutch pedal pretty much since day one when I got it but back then with the TBI 350, the issue was just a flat pressure plate then I replaced that with a used leftover Centerforce from the K10 when I did the NV4500 swap around 2012 using an Advanced Adapters bellhousing. Then in 2015 when the bear got its 8.1 swap I started with fresh hydraulics and a new Centerforce clutch and had the flywheel turned at our local driveline shop. After that swap was complete the bear had a ton of new power but the less than sterling clutch woes continued although they issue felt different.
I dealt with the poor clutch issue for years where it just felt like the release bearing wasn’t pushing the pressure plate far enough. It launched with a lot of chatter and grabbing reverse was near impossible without turning the engine off. Given how inconsistent Advanced Adapters quality is, I suspected the clutch fork pivot ball was in the wrong location, wrong ball or whatever so I decided to pull the AA bell and use a factory GM bell from a 1996+ with internal slave/release bearing, which also required a new clutch and PP. Being on a budget I chose to go with a run of the mill LUK clutch, which worked okay but wasn’t nearly a good performer as the Centerforce. Those changes did make a slight difference but still not enough to make the pedal feel nearly as good as the K10.
Fast forward to this past June, I decided to get a new Centerforce clutch kit for a 1996+ 454 but this time I decided to get a fresh flywheel since that is about the only thing I haven’t changed throughout all of the clutch issues that came to be after the 8.1 swap. As I pulled the old flywheel out and laid it next to the new flywheel it was a complete “AH, HA!” moment when I saw what the driveline shop did 7 years ago. Those clowns completely machined off the lip where the pressure plate rides. The amount of metal they took off was thicker than a quarter and certainly would make a difference in the dept of the release bearing push. The flywheel balancing holes are also on that same outer plane where they wiped those down too!
Long story short, the new flywheel fixed the clutch engagement issue AND the vibration issue that’s been driving me crazy for all these years…….and the Centerforce clutch allows the NV4500 to shift as close to a sports car as one could get. I totally didn't expect this flywheel to fix the vibration as the vibration felt more speed related than RPM related but then again I don't drive these 8.1s at 2500+ RPM at a constant pace in any other gear than 5th. So, for you 8.1L guys with manual transmissions be careful if you ever have your flywheel turned. Probably better off just replacing the flywheel rather than having it turned. Shame on me for not noticing the day I picked up the flywheel from the driveline shop back then.
Lip vs no lip
Centerforce on left and LUK on right
Centerforce on left and LUK on right
So, with that success I fell back in love with the ole bear and decided it needed more love so it inherited a hand me down old school Hickey Sidewinder winch that came off my K10 a few years ago, which was a hand me down from my dad's buddy that bought this winch brand new as a dealer installed option on his 1978 K20 way back in the day. It was quite the time consuming blacksmithing project reworking the brackets and skid plate designed for a 73-80 to fit an 81+ with much different frame horns and bumper shapes. Funny, these old winches used tiny 7/16 cable that was only about 2 feet long This time it got treated to 85 ft of 3/8 synthetic rope. I really didn't think a full 100 ft would fit on the spool. I'm still deciding on a hook though..thinking of a Warn Epic Sidewinder, a Factor55 dealeo like the one on the K10 or stay with nothing at all as it is now.
When the Sidewinder was on the K10
I restored an old period correct Warn bumper with a Warn 12k to replace the Sidewinder
Now it lives on the Polar Bear
I made some snazzy bump stops so the plate wouldn’t get pushed into the bumper driving on the highway
Solenoid packs
Winch neutral pull rod
100% Jeff Bezos Chinesium winch rope
Continued............
Larry
Bigassgas Explorer
Ran out of room in the last post
When I pulled it out from under the bench where its been hibernating for the past few years
It wasn’t pretty inside but wasn’t bad either. As far as I know, this lid has never been off since it was new. While filthy, it didn’t show an ounce of wear on anything.
It came apart and went back together so easy it was silly
Blasted and resprayed the skid pieces
This was the challenge….the frame horn difference between the 73-80 and 81+ were just different enough to turn a simple bolt on project into a blacksmithing project
I also really wanted to use the Engineered Vintage shackle brackets but the Sidewinder crossmember bolt was right ********** dab in the way so I used factory K30 hooks instead. No biggie, I'll use the EV shackle brackets on my K5 project later
With the winch all wrapped up it was time to deal with the steering wandering. This Dana 44 came out of my K10 about 10 years ago and the tie rod assembly has never been replaced since my 27 years of owning the K10. It was time for a nice HD ORD tie rod assembly. I modified their steering damper bracket with x3 1 1/8 saddle clamps and tossed their tiny ¼” u-bolts in the trash.
Next up is it goes in for an alignment next week then I found today that its ready for a new fuel pump. Its been hard starting lately and felt a little low on power only to discover the fuel pressure is only 35 psi! I usually set these 8.1s about 68 psi. And of course, the fuel tank is full. It never ends
When I pulled it out from under the bench where its been hibernating for the past few years
It wasn’t pretty inside but wasn’t bad either. As far as I know, this lid has never been off since it was new. While filthy, it didn’t show an ounce of wear on anything.
It came apart and went back together so easy it was silly
Blasted and resprayed the skid pieces
This was the challenge….the frame horn difference between the 73-80 and 81+ were just different enough to turn a simple bolt on project into a blacksmithing project
I also really wanted to use the Engineered Vintage shackle brackets but the Sidewinder crossmember bolt was right ********** dab in the way so I used factory K30 hooks instead. No biggie, I'll use the EV shackle brackets on my K5 project later
With the winch all wrapped up it was time to deal with the steering wandering. This Dana 44 came out of my K10 about 10 years ago and the tie rod assembly has never been replaced since my 27 years of owning the K10. It was time for a nice HD ORD tie rod assembly. I modified their steering damper bracket with x3 1 1/8 saddle clamps and tossed their tiny ¼” u-bolts in the trash.
Next up is it goes in for an alignment next week then I found today that its ready for a new fuel pump. Its been hard starting lately and felt a little low on power only to discover the fuel pressure is only 35 psi! I usually set these 8.1s about 68 psi. And of course, the fuel tank is full. It never ends
billiebob
Well-known member
Wow flashback.... I installed the Sidewinders in the 1970s.... not my favourite winch but still cool.Ran out of room in the last post
When I pulled it out from under the bench where its been hibernating for the past few years
It wasn’t pretty inside but wasn’t bad either. As far as I know, this lid has never been off since it was new. While filthy, it didn’t show an ounce of wear on anything.
It came apart and went back together so easy it was silly
Blasted and resprayed the skid pieces
This was the challenge….the frame horn difference between the 73-80 and 81+ were just different enough to turn a simple bolt on project into a blacksmithing project
I also really wanted to use the Engineered Vintage shackle brackets but the Sidewinder crossmember bolt was right ********** dab in the way so I used factory K30 hooks instead. No biggie, I'll use the EV shackle brackets on my K5 project later
With the winch all wrapped up it was time to deal with the steering wandering. This Dana 44 came out of my K10 about 10 years ago and the tie rod assembly has never been replaced since my 27 years of owning the K10. It was time for a nice HD ORD tie rod assembly. I modified their steering damper bracket with x3 1 1/8 saddle clamps and tossed their tiny ¼” u-bolts in the trash.
Next up is it goes in for an alignment next week then I found today that its ready for a new fuel pump. Its been hard starting lately and felt a little low on power only to discover the fuel pressure is only 35 psi! I usually set these 8.1s about 68 psi. And of course, the fuel tank is full. It never ends
Larry
Bigassgas Explorer
Meow
I agree, but its one of those bird in hand is worth more than 2 in the bush kind of things plus they are a pretty cool old artifact. Even though they were rated pretty low this winch has never let me down when it was on the K10, which I can’t say for the Smitybilt 10K on the rear bumper that either doesn’t work when you need it to or breaks every single time it gets used. Literally, Zoomad can contest…..it breaks every time it gets used no matter how straight of a pull
Thanks!
zoomad75
K5 Camper guy
My poor '75 K5 was on the end of the Sidewinder a couple of times. One of which pulled hard enough to tear the transmission cross-member where it was hung up on a ledge.
The '75 had been on the end of the smittybuilt cable too. The winch broke before the truck was rescued.
I think the Sidewinder with the synthetic rope should be unstoppable.
The '75 had been on the end of the smittybuilt cable too. The winch broke before the truck was rescued.
I think the Sidewinder with the synthetic rope should be unstoppable.
