NBS 5.3 - common maintenance parts?

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xjsc16x

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I have an 02 Tahoe LT 4x4 that I am in the middle of putting a transmission into. While I have it off, I could clearly see the rear main seal needed replacement.

So far I have replaced:
-Steering parts when I bought the truck - inner/outer tie rod ends, center link, pitman and idler arms, idler pivot, also front sway bar links and bushings
-Bought a rebuilt transmission to put in
-Front seal of transfer case
-Neutral Safety Switch and the big plug that goes to it (broke whole taking it off)
-Ujoint for rear driveshaft (cap popped off and lost the needles)
-Rear main seal and rear plate gasket kit, oil pan gasket, oil cooler block-off gasket
-Remflex exhaust gaskets

Went Felpro everything else.

Anything else I should replace while I'm into this thing? I can tell it needs shocks but I'll worry about that later.

Someone on the Facebook group suggested I replace something in the tcase (the pump I believe) but I didn't want to split it.

As far as I know I've covered a good amount of maintenance and common problem parts that I need. All new fluids as well.

-Justin
 

6speedblazer

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I would add slip yoke seal on the back of the t-case. Seems like they always leak after a trans R/R
 

PG01

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Dont those t cases have the rub through problem? There is a shield or something that goes inside to block something from rubbing through from the inside out. Pretty sure it was early nbs..
 

Chubbs

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If the transfer case is on the ground, you want to open it and swap in the upgraded oil pump plate. Do a Google search and check into the number of casualties resulting from that broken oil pump plate and see if that doesn't change your mind. its called "pump rub" in most circles and using that in your combo of keywords should provide enough hits to peak your interest. You will also find some testimonials in YouTube.

Do you know if there are any fault codes? check engine lamp?

check the front half-shaft seals for leakage and determine if the bearing/seal R&R is necessary. If you forego that exercise, consider using conventional gear lube in the front diff. GM actually spec'd conv oil for the front and 75-90 synthetic in the back diff. this is what I did, but I still have to go and top-off the front every 120-days b/c those seals need replacing.
 
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xjsc16x

xjsc16x

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I would add slip yoke seal on the back of the t-case. Seems like they always leak after a trans R/R

Will do. Thanks.

How many miles on it

200k+ can't remember off the top of my head and the gauges and battery aren't currently in the truck

Dont those t cases have the rub through problem? There is a shield or something that goes inside to block something from rubbing through from the inside out. Pretty sure it was early nbs..

If the transfer case is on the ground, you want to open it and swap in the upgraded oil pump plate. Do a Google search and check into the number of casualties resulting from that broken oil pump plate and see if that doesn't change your mind. its called "pump rub" in most circles and using that in your combo of keywords should provide enough hits to peak your interest. You will also find some testimonials in YouTube.

Do you know if there are any fault codes? check engine lamp?

check the front half-shaft seals for leakage and determine if the bearing/seal R&R is necessary. If you forego that exercise, consider using conventional gear lube in the front diff. GM actually spec'd conv oil for the front and 75-90 synthetic in the back diff. this is what I did, but I still have to go and top-off the front every 120-days b/c those seals need replacing.

Crap. That's what the guy on Facebook was trying to tell me to get. Merchant Automotive pump upgrade. I'll look into it tonight, but how hard is it to crack it open and change the pump? Is that going to require me replacing a bunch of bearings and seals and stuff?

No current codes but I did notice through the use of monitoring in the Torque Pro app that when I was doing a specific speed on the highway (like exactly between 65 and 70) cylinders 5 and 7 were misfiring. I already have new 'delco plugs and wires to put in and hopefully that is no longer the case once it's back up and running. I have an old thread on it here somewhere.

Thanks guys,
-Justin
 

Chubbs

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Crap. That's what the guy on Facebook was trying to tell me to get. Merchant Automotive pump upgrade. I'll look into it tonight, but how hard is it to crack it open and change the pump? Is that going to require me replacing a bunch of bearings and seals and stuff?

at the very least, you need to replace the 2 output seals, properly examine the output bearings, and give everything else a good once-over. you will need to replace the transmission output seal for sure.

you only need the finest circlip/snap ring pliers that you can buy. there is a stout clip that must be removed before the rear case half will come off of the rear output shaft. (see YouTube, lots of tutorials) Then your everyday socket/ratchet, etc. GM spec's 'anaerobic sealer' as the gasket for the 2 case halves going back together. don't use cheap RTV, and don't OVER-use anything; the gasket material breaks off inside the case and stuffs the oil pickup.

No current codes but I did notice through the use of monitoring in the Torque Pro app that when I was doing a specific speed on the highway (like exactly between 65 and 70) cylinders 5 and 7 were misfiring. I already have new 'delco plugs and wires to put in and hopefully that is no longer the case once it's back up and running. I have an old thread on it here somewhere.


Thanks guys,
-Justin

plugs and wires.. too easy. necessary, but too easy. most likely the intake manifold gasket needs replacing if you haven't done that already
 
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xjsc16x

xjsc16x

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at the very least, you need to replace the 2 output seals, properly examine the output bearings, and give everything else a good once-over. you will need to replace the transmission output seal for sure.

you only need the finest circlip/snap ring pliers that you can buy. there is a stout clip that must be removed before the rear case half will come off of the rear output shaft. (see YouTube, lots of tutorials) Then your everyday socket/ratchet, etc. GM spec's 'anaerobic sealer' as the gasket for the 2 case halves going back together. don't use cheap RTV, and don't OVER-use anything; the gasket material breaks off inside the case and stuffs the oil pickup.



plugs and wires.. too easy. necessary, but too easy. most likely the intake manifold gasket needs replacing if you haven't done that already

Watched a video last night, forget by who, but looked pretty simple really. I assumed that splitting the case meant having to replace bearings and such but the case half jut slides right off and everything stays in place.

Got the upgraded pump in today (comes with the sealer and a gasket) and waiting on overnighted output seals to throw it in.

As for the misfire, who knows but if it is still there after all this then I will just save myself the hassle and find a TBSS/07+ intake and swap that in while I'm at it. It was already on my bucket list for this truck.

-Justin
 

JollyRoger01

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The NBS problems that I see through the shop I work for aside from what you have already done is Water pump, fuel pump, parking shoes, knock sensors (harness, cover gasket and 2 sensor seals) quick disconnect connectors for the heater hoses, A/C belt tensioner, driver side front body ground (abs codes) front axle seals, diff actuators on occasion and rear ends.

The "pump saver" for the Tcase is a good idea.
 
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xjsc16x

xjsc16x

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The NBS problems that I see through the shop I work for aside from what you have already done is Water pump, fuel pump, parking shoes, knock sensors (harness, cover gasket and 2 sensor seals) quick disconnect connectors for the heater hoses, A/C belt tensioner, driver side front body ground (abs codes) front axle seals, diff actuators on occasion and rear ends.

The "pump saver" for the Tcase is a good idea.
That's a nice list of parts right there! None of which I intend to replace right now [emoji23]

I actually don't have a parking brake right now. Replaced a cable that was broken when I bought it. Stepped on the pedal, it was so stiff the pedal actually bent! I assume I probably need both rear cables (frozen) and to pop off the rear rotors and take a good look at the shoes. And maybe a new pedal.

But I appreciate the list, I will definitely keep an eye out. Going to be swapping to efans eventually so I'll have a good look at the water pump while I'm in there.

-Justin

Sent from my SM-G930V using Tapatalk
 
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