Jump to content

Recommended Posts

Posted

My 4l60e is starting to show its age a bit. Not ready to condemn it yet but it occurred to me that it would not be too difficult (on the scale of trans swaps) to put a NV4500 from a GMT-800 HD truck in place of my 4l60e. 

I've done a bunch of research on which part numbers I would need and it seems mostly manageable but I have run across something I can't find the answer to online.

My NP246 transfer case has the 27 spline input shaft because it's currently hooked up to a 4l60e. The NV4500 has a 32 spline output and was never (as far as I can tell) offered with a NP246, just the NP261 it seems like. However there's a part number for a 32 spline input shaft for a NP246. If I install that input shaft, will I be able to put my NP246 behind a NV4500?
 

Posted

Upon further research, I think it looks like the 32 spline input was installed in NP246 cases hooked up to a 4l80e in the 6.0 trucks. That means the 32 spline end would work with the NV4500 correctly but I still don't know if the planetary end of the input shaft is the same. 

NP246 cases with the 32 spline input are technically called NP246HD...

Posted

I think it's much more involved than swapping transfer cases and trannys. The computeror some kind of transmission control unit is going to want to know what happened to the 4L60E. I'm sure the 80 talks a whole new language. This job was easy on a 1964 Impala, a real pain since 1986 or so.

Posted

Well I'm not planning going to an 80. I'm scoping out going to a NV4500. 

I've seen that if you leave the PNP switch in Park, unplug the 20 pin, and seal it up with a plastic cover, the TCM basically just thinks nothing is up.

The VSS is in the transfer case so not an issue there.

The transmission temp sensor (on 4l60e only) and the reverse lamp switch on (NV4500 only) might give me some grief but I'm doing research still.

Posted

You don't have a TCM you just have a PCM. You will need a tune to tell the computer that your truck is a manual now

Posted

Right, yeah. I used the wrong acronym. 

I do expect to eventually tune the truck (if/when I install the manual, I'm pretty tired of my 4l60e) but I've been reading other forums and it seems like other people who swap manuals into their GMT800 trucks have very few electrical problems even before the tune

Posted

The question I actually have is about transfer case/trassmission interfacing. I was hoping to confirm that the 32 spline transfer case input shaft is a drop-in replacement for the 27 spline shaft. I'm hoping I don't also need to buy the low range planetary set but if I do, I would want to know before I had the case apart on my bench

Posted

I'd be surprised if a whole new transfer case is cheaper than an input shaft and a set of clutches and steels. I'm sure it would be easier but I'm more budget-constrained than time-constrained

Posted

Maybe go on performancetrucks.net and ask this question or gmfullsize. 

A few dudes on those sites have swapped manuals and I would suggest try those sites and ask

  • 2 years later...
Posted

If this ever gets seen I wanted to share that the few fellas I’ve seen pull this off was with stand alone ECU and the other had to incorporate a “piggyback” that also controlled the transmission parameterswhich was only done with quite a bit of custom tuning by way of some software wizardry….if you would like I can try n look for their contact info if you’d like….although its been nearly 8-9yrs back so I can’t promise much sir…👍🏻

  • 5 months later...
Posted

Is there any way to post a step by step process of a 2wd I'm currently trying to figure out what to do with getting the transfer case to work but ebay has the 32 spline input and the aluminum spacer and it all goes together easy. If anyone knows if it's possible to convert this tcase to a manual since the pcm ran every little movement of that thing. I'm stuck right there that's the last thing I gotta do to have it fully functioning. 

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Latest Articles

  • Posts

    • Thanks - I wasn't quite caffeinated this morning. 2:1 makes sense, turning the crankshaft 360 degrees will turn the cam 180 degrees, and had I done that, the cam's dot would be at 6 and the crank's at 12 again.   I went ahead and took the sprocket off anyway, aligned everything dot-to-dot including the balance shaft just for s&g. I'm glad I did because I discovered no Loctite on the timing sprocket bolts. Maybe it's not required, but at only 20 ft-lb torque spec, those bolts aren't in there very tight. Cleaned and reassembled with some thread locker and torqued.   A general observation: Less is more with RTV. If a little doesn't stop a leak, a LOT probably won't, either. RTV is thinly veiled revenge, in a tube...      
    • The timing marks are ok, that is #1, you can turn it over until they line up and it won't change anything, the crankshaft turns twice for every camshaft revolution, I have always set up SB Chevs as your pic shows using a straight edge
    • Someone's been here before.... There is a receipt for a 3-piece timing set, purchased earlier this year.   Is this picture something, or, nothing?   I have the timing cover off and my crank is perfectly TDC and the keyed gear's locating mark is dead on 12 o'clock.   The cam gear locating mark is also at 12 o'clock. Now, I'm not an expert, but all the install guides say the two locating marks should meet and be perfectly aligned when installing a timing set. The mark on the crank should be dead on 12:00 and the cam gear's mark should be dead on 6:00, and both marks should be perfectly vertically aligned.   I believe the timing gear is keyed or has a dowel that ensures it can only be installed on the cam in one position, so I have to believe the cam is out of phase somehow. At the very least, with a triangular bolt pattern, it can only be installed in one of 3 different positions.   Before I pulled the front cover, the truck was running alright, no service engine soon lights except an occasional P0172 / rich condition. Timing -16 timing at idle (should be +16), and total -35% fuel trim, two conditions I haven't been able to figure out.   In related news, my injector tested pretty well, wasn't leaking, but I had it rebuilt anyway, and it's on it's way back to me.         Along with this discovery, the good and bad:   Good: The oil pan seal appears undamaged.   Bad: -The timing cover has been reused, and the positioning dowels have been broken. That could explain some of the leaking. -Some kind of white paste or grease was used to try to seal the oil pan seal and timing cover (since wiped off..). -Then, someone globbed silicone all over the front of the cover and also buried the ckp sensor in it. But, they didn't put any inside the cover or use RTV to try to seal the oil pan seal with the timing cover (good).
    • The guy that owns K&P filters last I checked in with him has over 300,000 miles on his Dodge base Hemi using his own 35 micron absolute stainless mesh filter from its first oil change.    The GM study I've posted a dozen times shows the relationship in engine life based in multiples of base units, not miles or years. That is the base unit is the number of miles the motor ran using the reference filter efficiency.    The above two paragraphs dismantle anecdotal arguments IF one changes oil often enough to prevent particle formation and the motor is in otherwise good shape. That is not full of silica (no air filter) or suffering a metallurgical issue that is not part of the lubrication discussion. Poor heat treat in example.   Data from UOA's I've reviewed from more than a few engines can show remarkably broad variations in oil cleanliness using the exact same filter over the course of an engines life.     Lastly there is the common sense of it. Wear debris WILL circulate the engine BEFORE it ever sees a filter in route to that filter and WILL harm the pump which NEVER sees filtered oil.    Alpha question then becomes, given the facts, how long do you believe is a reasonable service life from a vehicle you are certain you will not pass down? That is the junk yard will be it's resting place when you're done with it? (the moral issue most don't care about).    Omega question is then how diligent are you prepared to be in general mechanical, air & oil maintenance? Preventing particulates and keeping them sufficiently dilute; preventing the precursors from generation, amalgamation and precipitation.    If I get a good look at the engine bay of a vehicle I have a fair idea of the owners commitment to the inside of the power train. That 30 micron WIX is still more efficient than a sieve.                 
    • It also depends on what criteria someone is using for “best” when talking filters.  Are we going off best efficiency?   Best quality/QC?  Etc. because the two may not mutually exclusive.  
  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...