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Project Polar Bear: '89 V2500 Suburban

I'm so sick of the yearly NV4500 rebuilds on this and the K10 I'm seriously considering a 4L80E for the Polar Bear.

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But I do like my 4L80E...

David
 
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Larry, what are you running for an AC condenser in that beast? It's gotta be huge to handle all the heat from the cab and engine compartment. (ambient temp)
 
Larry, what are you running for an AC condenser in that beast? It's gotta be huge to handle all the heat from the cab and engine compartment. (ambient temp)

Whatever the stock condenser is. It actually doesn't look any different from the condenser in my K10 but I have really studied them either. The A/C works great in both trucks for sure and will freeze you out on a 105 degree day in the desert! :waytogo:
 
Sucks about the nv4500! Wonder why it's giving you such fits? Have you considered just buying a new one off eBay? If I remember right they have brand new ones on there for about $1600.
 
Sucks about the nv4500! Wonder why it's giving you such fits? Have you considered just buying a new one off eBay? If I remember right they have brand new ones on there for about $1600.


Yeah, in fact the NV4500 in the K10 is one of those from Ebay. A real nice seller out of Texas. It turned out to actually be a NOS 2006 2500HD transmission that had never been used (I learned later the cover is also different on the HD trucks vs. the non-GMT-880 trucks. 260 hits on this thread and not one single comment. I guess everybody already knew the covers were different :rolleyes:). Hell, it still had the OEM fluid in it too. It was $999 with a $500 core (in 2010) and I sent them back a fried Dodge NV4500 my buddy had sitting in his iron pile at his shop as a core. The bad thing is I cut the mainshaft on that one to accommodate the Advance Adapters 205 kit (big phucken mistake!) then about 3.5 years later 5th gear started screaming so it had to have its first mainshaft, 5th gear set and that time I went with a round pattern 205 and got rid of the AA kit. Here is a very hijacked and bastardized thread on the NV4500 capers into the K10. I linked this to the portion of the thread that covers the 2nd NV4500 that was is the Ebay sourced NOS NV4500. Post 284

The NV4500 in the Burb is the original one I had in the K10 before the Ebay sourced trans that was supposed to be a good used one. Within 10 miles of driving it after the initial install it was obvious that one needed a 5th gear set too so I yanked it and ordered the ebay one above. When it came time to swap out the SM465 for a NV4500 in the burb I had the original NV4500 out of the K10 reworked and when I got it back it was a sumbish to stab in 5th gear. 2 years later I had it reworked again and now it is actually worse where 3rd gear is a sumbish too once it gets warm. Getting feed up with these damn 4500’s but I know if I go to a 4L80E it will just be something new to piss me off down the road as well.

Funny you should mention the Ebay transmissions as I was actually thinking of ordering an early NV4500 with the 6:54 granny gear to stick in the K10 then move the K10’s perfect shifting 5:61 granny gear 4500 to the Burb (I really miss the deep granny gear in the K10 that sees aot more off-road action). The only problem with that idea is the trans rebuilders I’ve found so far are short on early 4500’s and want an exact core in return. In other words, they wouldn’t accept my later 4500 as a core. We’ll see, got a lot of irons in the fire before I start worrying about that just yet. The vibration and leaky radiator need to be dealt with then figure out what I want to do about this damn Raylar cam. Either remove it and go back to stock or try to find a better tuner. It runs like a rapped ape at wide open throttle but the normal drivability isn’t nearly as smooth and clean as the K10. After the last session with the tuner it came out with an annoying idle flare when up shifting as I step on the clutch. This flipping Suburban has been a pain in the ass compared to the K10. I often regret the cam until I out run a diesel truck then that brings a smile back to my face…that is if I can get the sumbish to take 3rd gear :haha:. Then again, I could keep the cam and swap in an automatic and have much of the tuning issues handled. Tuning an auto is much easier than a manual due to the wide range of RPM and load ranges manuals see. The constant load of a torque converter smoothens things out. I fixed my FILs TBI 454 in his little Sportside by ditching the 5 speed and going to a slush box. Eagle Mark had a much easier time tuning the engine once it had an auto.
 
Hate it when stuff gets all complicated and you have to wrack your brain about which direction is best to go. I have to imagine your tuning issue has a lot to do with the tuner. After all, they had 8.1/manual Trans from the factory. Should be easy enough to take that tune and dick with it a little. Your cam seems like a perfectly tuneable cam. The thing I also hate is having the lingering feeling in my mind taht maybe the cam isn't to blame. Like maybe I have a vacuum leak and would have a similar problem even if I had a stock cam in it. But no way of really knowing but always wondering. It's a wildly unpleasant feeling.
 
Hate it when stuff gets all complicated and you have to wrack your brain about which direction is best to go. I have to imagine your tuning issue has a lot to do with the tuner. After all, they had 8.1/manual Trans from the factory. Should be easy enough to take that tune and dick with it a little. Your cam seems like a perfectly tuneable cam. The thing I also hate is having the lingering feeling in my mind taht maybe the cam isn't to blame. Like maybe I have a vacuum leak and would have a similar problem even if I had a stock cam in it. But no way of really knowing but always wondering. It's a wildly unpleasant feeling.


Right, there’re indeed factory manuals with 8.1Ls. I’ve got a factory 8.1L in my Silverado and the K10 works perfectly with a manual albeit a stock cam. My two rigs run on 5.3L/6.0L operating systems (for mechanical throttle body) on 0411 ECMs with L18 bin files by way of Howell. The Burb has the same calibration as the K10 but the Burb has been reworked by the tuner for the sake of the cam. There are no vacuum leaks. Keep in mind, I am not a shade tree mechanic or a hobbyist. I do this crap for a living. Checking the simple stuff was the first place I went. That said, you could say there is an air leak causing the idle flare which is somewhat a true statement but it is a controlled air leak by the IAC due to the way the tuner has things set up. The tuner is most likely my biggest issue here but where I live there isn’t many tuners around as I mentioned before. He keeps blaming the wide lope separation of the cam and high altitude (We’re a tad above 5,000 ft. here) plus the difficulties in tuning a vehicle with a manual trans. If l lived in CA, AZ, TX or even back in Detroit it would be no problem as there are plenty of good tuners around. Southern Colorado, not so much. Bunch of flakey bastages around here! Got to spend some time and think which way I want to go with it…..cam swap, trans swap or figure out a different tuner. I’m about done dealing with tuners. Between working with Eagle Mark on a TBI project and these asshats on this 8.1L I don’t really want to deal with a tuner ever again. Very eccentric people those tuner types guys are. They are like odd duck IT guys with minimal mechanical knowledge :haha:
 
Time to buy a hptuners setup and just do it yourself?

Screw that! I ran the 8.1L in the K10 on a RamJet 502/Marine MEFI-4 system for the first year before moving it to a 0411 ECM on a Howell harness. I dicked around trying to tune that MEFI-4 system myself and found I am not a tuner type guy. Leave the tuning to the so called “professionals” :haha:
 
Are you still happy with the fierce tires? Or if you had to do it again would you go a different direction?
 
Are you still happy with the fierce tires? Or if you had to do it again would you go a different direction?

Ah, yeah….good tires but when Goodyear Duratracs are the same price (and sometimes even less depending on the deal of the day) it is hard to pass up Duratracs for Fierce. I love both the Fierce and Duratrac about the same so it would come down to the deal of the day as a deciding factor as which to buy again. Too soon to know which will hold up longer.

We have 3 rigs around here now running Duratracs…..The Polar Bear is currently wearing the K10’s Duratracs, the Silverado has a fresh set of 285 Duratracs and Rob’s Zook5.3 project has a fresh set of 315 Duratracs as well.
 
I may have missed this so if you said it earlier in your thread I'm sorry. But I know you swapped the NV4500 into this thing before the 8.1 swap, but when you finally swapped in the 8.1, did you use the same flywheel/clutch setup that was on the back of the TBI350? I guess my question is are all those flywheel and clutch's interchangeable with the 8.1 to work with the NV4500?
 
I may have missed this so if you said it earlier in your thread I'm sorry. But I know you swapped the NV4500 into this thing before the 8.1 swap, but when you finally swapped in the 8.1, did you use the same flywheel/clutch setup that was on the back of the TBI350? I guess my question is are all those flywheel and clutch's interchangeable with the 8.1 to work with the NV4500?
I used the same Centerforce DF024909 clutch kit on both the 5.7 and 8.1 but when the 8.1L was installed I had to purchase an 8.1 specific flywheel (12582964). BTW, that particular Centerforce kit will only work with mechanical clutch or hydraulic with externals slaves. If you’re using a later NV4500 with the integrated slave/release bearing you would need a different part number.
 
I used the same Centerforce DF024909 clutch kit on both the 5.7 and 8.1 but when the 8.1L was installed I had to purchase an 8.1 specific flywheel (12582964). BTW, that particular Centerforce kit will only work with mechanical clutch or hydraulic with externals slaves. If you’re using a later NV4500 with the integrated slave/release bearing you would need a different part number.

If I use the AA bell adapter to use the external slave, then that should be the correct part number right? I just picked up a 1997 gm NV4500 4x4 and was planning on using that adapter anyways.
 
If I use the AA bell adapter to use the external slave, then that should be the correct part number right? I just picked up a 1997 gm NV4500 4x4 and was planning on using that adapter anyways.

Yesiree, if you use the AA Bell kit 712576, AA slave bracket 715535 the Centerforce DF024909 clutch kit is compatible but you will need to open the holes in the pressure plate as the pressure plate to flywheel bolts are larger on the 8.1L flywheel. Just use a step drill to open them up one size.

I don’t know how dead set you are on Centerforce but I noticed the DF024909 kit is getting stupid expensive. Like $400! Just a couple years ago I paid $315 for the same kit and I even thought that was a hosing. I actually have the 8.1L out of the burb now replacing the cam shaft and ordered up a fresh Centerforce pressure plate to throw in while the engine is out as I bent some spring fingers when I put the engine in several months ago. I planned to just buy a new clutch kit until I saw the price so I just ordered a pressure plate by itself and it will still stupid expensive at almost $300 just for a pressure plate! Prices are getting out of control! Next time I’ll probably look at alternatives to a Centeforce just due to cost. That said, I’ve never cooked one of these though. They hold well and have great pedal feel

Christmas vacation wrench-a-thon! Rob on his K5 and me on the Burb
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Rob getting after the rear window gremlins
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We will see what I end up doing with the actual clutch itself. I am looking for an 8.1 liter first before ordering clutch parts, but that is some good info. If prices all over seem to suck I will just spread out the purchases and buy things a couple weeks apart (flywheel one month, clutch kit the next, ext... :D). Thanks for posting up all the part numbers too...that is a huge help. Love the burb!!
 
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