NV3500/Getrag Reference thread!?

[Roostboy102]

I was just wondering if there is anyone with definite answers on what's needed to put the old getrag 5 speed behind the ls engines? Should I not look for the old style? Should it be the nv out of the newer chevy trucks? Is the hydro throwout bearing better than the old slave cylinder setup?

I understand that the newer NV3500 is a direct bolt up and you would just use 4.8 parts and be ready to roll. I found a good deal on the older style (out of a 91 truck) and just wondering if it's worth the hassle.

All the info I've found thus far is a bunch of discussion but not a whole lot of cut and dry facts! JW if anyone has these facts

Thanks guys!

[Dustytrix]

I went thru the same issues, I never got a for sure answer either. If I remember correctly I found a lots of info on LS1Trucks.com you might be able to get some info that will help there. I ended up going with 4l60e because of lack of info.

[Roostboy102]

Thanks! I'm determined to have a stick in my truck and don't have the dough for T56 or TKO so I'm stuck with the truck 5 speed! N I'll be darned if I'm not going to figure it out! Just thought id ask for suggestions first
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[CSGAS]

I plan on doing this swap during Spring Break.

So far I've noticed most of the NV3500s on eBay are for 4wd, so plan on going through a dismantler or a rebuilder (or both to cut down on the core charge) to get a 2wd model. I also intend to use a hydraulic throwout bearing setup just to reduce clutter and open up space for a true dual exhaust tucked up above the bottom edge of the frame rails, out of sight. If you use any post-86 engine casting, you'll have to count on using at least a hydraulic slave cylinder setup. Blocks didn't come with mechanical clutch bosses after then. Also watch on your Getrag/New Venture selection, where the opening is for the hydraulic setup. Some bellhousings have the opening on the passenger side, intended for a slave-and-fork setup over there but I have to believe that's the best time to convert to a hydraulic throwout instead.

Stock truck clutch master cylinders don't look like they will fit behind a brake booster unless the booster bracket extends pretty far into the engine compartment. I have seen pictures using the F-body (T-56) master but I am going to look at some of the ones used in fwd applications, that point at a downward angle. I know, that's not much help, especially not knowing what brake setup you plan on using, but it's what I'm going to do.

I'm also planning on using a trans crossmember from a 73-87 truck, but in a pinch I think the stock 3-speed (forward) crossmember can be slid back and drilled for the mounting pattern--it should even hang lower which would correct for the height vs driveline angles.

The S-10 version has a longer tailshaft. I was going to take advantage of that fact to swap to a single-piece driveshaft but I think now that's more practical for a Blazer or shortbed. The half-ton truck version might go in without any driveshaft cutting--we'll see.

I'm going to try to get a high-hump just for the "finished look," but all the extra bulk in the NV3500 is below the centerline, and I know how to use a sledgehammer if it hits the floor. I'll keep the stock shifter while debugging the installation but there's an eBay store supplier who makes copies of the Hurst shifter that used to be available, that allows any 2-bolt arm to attach...that'll be later, during the "dress-up" phase.

I also intend to swap in a "junkyard sourced" speedometer to deal with the sensor issue. VDO and Autometer were supposed to have made the IROC and SRT speedos, respectively, which should also mean those are programmable if I don't find a programmable one at a swap meet (the Classic Instruments one looks a lot like the stock gauges). Otherwise I'll try to get the instrument cluster from the same truck as the NV3500 and remove the circuit board from it. I am confident in my abilities, to be able to insert the mechanism behind the stock faceplate...I just hope the odometers are compatible without using a computer. Last choice will be a SunPro (ie cheap) or Ultra-Lite II (my favorite style) speedo at full price, again in the stock cluster but maybe using a 70 Corvette faceplate (the MPH tickmarks match using the same typestyle as the C-10) depending on which option I can afford. Lots of choices.

I've read some Dodge NV3500s are compatible, but from what I've seen in dealerships (during warranty inspections for other reasons) I won't try to make the changes needed to use one. If I need spare internal parts I wouldn't mind sourcing a Dodge version though. I am a little concerned that the New Venture transmissions seem to need special tools to disassemble (relative to the T-5s which can be done with standard tools and spring-clip pliers). That's not enough to convince me to change my plans though.

The back-up lights use a later connector, I plan to get the extra length of that harness to make it easy. The speedometer plug is similar, but also has provisions for the ABS system to get input. I'll find out if that causes any difficulties when I get to it, but I recommend getting that harness & plug anyway.

The number one reason I am not stepping up to a T-56 style, or to a NV4500, is weight. I know I'll be doing this swap by myself (with a jack, ramps, jackstands, etc) and that really left the T-5 and NV3500 as the only OD manuals as choices that I can hoist into position safely by myself (there will be someone around to dial 911 if I crush my head but they aren't in a condition to help out underneath any vehicle). The two lighter aluminum OD choices weigh about the same as the iron Saginaw I'll be removing; the stronger ones are about 50 lbs more.

I'm not sure yet if I'm going to rent/borrow a commercial hydraulic clutch setup tool or fabricate one of my own out of bar stock and all-thread...yet. I will use a new flywheel (ordinary 153 tooth for two-piece seal to match my current engine and the starter I will use, hopefully a service replacement style reduction starter instead of the nose-less aftermarket ones) and a 26 spline clutch that works with the pressure plate that I replaced too recently to want to give up on yet.

If it sounds like, "There should be more to it," then you know why I selected this option over the T-5. This should be--should be--a relatively easy bolt-in that I can do in less than a week and have time leftover to debug the setup before I have to count on it (my truck is my DD). Of course, I've done some tranny swaps before so I can count on the stuff that I have to predict s long as I have the major parts I know I need, ordered and can get to the parts store for the rest. You probably don't have to have your truck back up so quickly, so you can either wait for me to be the guinea pig or dive in and get as far as you can.

There are a lot of transmissions that can be confused with the NV3500. Make absolutely sure you don't end up with the Aisin version. Think of it as the Chinese copy that's more expensive than the German version. I know that there are improvements for reliability (shaft materials and synchros mostly) in the later NV's that I doubt are in the earlier Getrag version. I intend to make sure I get the actual New Venture trans just so I know I can get service parts that are compatible and relatively inexpensive if I need them, but I made that plan without looking closely at any Getrag version so I don't know if the latter has anything that would give it an advantage over the New Venture one. I lost a little bit of confidence in Getrag in general, too, after seeing their IRS rearends break so much under stress in Corvettes, Camaros, Mustangs, and Challengers. I plan on using my truck as a shop truck so it will be under stress once in a while.

If you're going to have help though, you may want to consider the NV4500. It uses a separate bellhousing, is higher rated, will work with the same clutch setups, but the dimensions should be larger all around. The NV3500 is rated for 300 ft-lbs torque input, but that rating was set at a time that a safety factor of 1.5 was probably in use during engineering--that means personally I'd trust a fresh one in good condition up to 400 ft-lbs, but it'll probably give up at 450 and a worn trans or worn synchros will reduce that. The T-5s on the other hand were engineered at a time when "marginal design" was employed, so 300 means 300 as far as I'm concerned. Remember that same time frame is also when the Getrag version of the trans was engineered, but that's still not a specific experience. The 4500s are rated for--surprise--450 plus a safety margin. I haven't had to inspect either a 3500 or a 4500, and that goes for both Getrag and New Venture versions.

[Roostboy102]

Thanks for your input CSGAS! I just picked up the 5 speed today. It was out of a 91 2wd. It sounds good turning it through all the gears and felt solid. I got everything with it (slave, master, shifter, bolts, flywheel, clutch....) for $300 from a standup guy. So I'm all in now going to make it work and can't wait to drive it!

If I do understand things correctly, I'll need the 4.8 flywheel with a matching diameter clutch and pp corresponding to the original vehicle as well as the starter!? So another question. Is the 4.8 flywheel the same diameter as what wouldve come in a 91?

[whitels1]

What I used was a LS7 throwout bearing, nfw1050 flywheel and the standard old clutch.

http://67-72chevytrucks.com/vboard/s...0&postcount=18

[Roostboy102]

Can anyone confirm or deny that I'll need the ls7 pilot bearing or Dorman 14659 bushing? Think I have all my ducks in a row except this little detail! Thanks guys
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[CSGAS]

This discussion may answer your question:
http://ls1tech.com/forums/13187274-post20.html
I take this as meaning the Dorman bushing is your best choice, I do not know if the LS7 pilot is extended. However, check below about the input shaft differences.

Also I may have to rethink my plans. One, I haven't been able to get my parts together as quickly as you did (btw, when I posted I hadn't looked at the forum group, I'm keeping an old Gen 1 engine with mine).

The trans you got has 3 or 4 shift rails instead of just one, right? That makes it a "5LM60" as opposed to the NV3500. Same internals though, and more importantly to you the input shaft is 5/8" shorter than the NV3500. If you have a pre-2001 engine, then the crank flange is intended to work with that shorter input shaft. If you have a 2002+ engine then the spacer and everything else is involved, or using a trans meant for the shorter crank. The flywheel mentioned in the link, which is supposed to be the one you originally read about, appears to be used to make the short crank 2001+ engines mate to the long input shaft NV3500s, then went out of service when that trans also did.

We haven't thought about what your engine came from, and that could simplify the pilot issue.

Also, the VSS output on your 91 trans should be 2000 ppm, which is supposed to work with the S10 speedo gauge conversion similar to the one shown here http://67-72chevytrucks.com/vboard/s...d.php?t=512751 except get it from a stick shift S-10 or similar.

Personally, I have to rethink what I'm going to do...it doesn't look like the parts are coming together in time for the week off I'll have, plus these are a couple issues that working around, will probably take more than a week unless I get lucky. We'll see!

[Roostboy102]

I used the dorman and she's all together now. Just gotta get my second bolt thru the dirty dingos... Also, I think I'll just use a GPS speedo for ease of install.

[Bandit78]

Im new on the board but Ive been looking every where for info on a swap like this. I have a NV3500 out of a 2000 S10, an thats Just about as far along as Ive got. I want to swap in into my 69 c10 an take the 4 speed out. I no Ill need to put in the hydraulics for the clutch, but I cant nail down what it takes to actually mount the NV3500 to the first gen SBC.

Can yall help me out on what all Ill need to mate the two together or what to look for to get started? Its a great thread and so much Info