H2 Manual Transmission Swap

[rao]

I am pretty sure this is the first one anywhere

Supercharged Hummer H2 with every conceivable suspension and other upgrade now has a NV4500 manual transmission and a manual transfer case, all from a 3/4 ton Silverado.

Now it is no longer full time AWD, but can be switched into rear wheel drive for very impressive smoky burnouts (which it does quite well) and almost 50% better gas mileage than the race-built 4L65E auto transmission. It was done because the truck had gone through three 4L65E's and kept breaking tail shafts and the owner wanted a real transmission



Note smoke from the back tires only and how the truck is starts to rotate and then straightens out







and yes that is how clean the truck is after we worked on it.

The NV4500 and NP263 went in without a hitch. The only real trouble we had was the clutch pedal. The dash on the H2 must be different from the Silverado and the clutch pedal bracing wanted to go where the Body Control Unit was. Not to hard to fix, but it took a while.

[rao]

Clutch Pedal and Manual Transmission Brake Pedal



Shifter - a short shifter was made using part of the stock manual transmission shifter and a tie rod end to provide the correct geometry to shorten up the shifts. He hasn't finished up the custom console yet, but the cupholders willsitill fit and it will look stock when it is all done







Transfer case shifter. The handle needs to be modified so that it comes out on the outside of the center stack, but that is a no-brainer



The NV4500



I am also selling the auto transmission, transfer case and other odds and ends that are no longer needed.

[DRTYFN]

What inspired you to do the swap?

[rao]

The owner kept breaking the output shaft on the auto transmission (the car was on it's 3rd transmission, a very expensive fully built racing type, which wasn't all that pleasant to drive) and any upgrade would have required a different transfer case (you an do a 4L80E to the Hummer xfer case but the output shaft on the 4L80E has to be turned down defeating the purpose) and he wanted a manual transmission.

[Desert Dan]

Great Job and Gearbox.
The NV 4500 has a granny low!

I wish GM offered a 5-speed option from the factory

[rao]

1st is definitely a granny gear, especially in 4WD Low . Starting in second is the way to go.

[Alt-F4]

How much stronger is that set up over stock ? How much does something like that cost? I like it

[rao]

The transmission is much stronger than stock; the NV4500 transmission is rated for 14.5k lbs gross vehicle weight. The swap was not inexpensive, especially since we used all new parts. I'd guess the cost was over $6k in parts.

[iccon]

Nice Job

[BLOWNZO6]

Very cool and not a big expense if you consider the abuse that thing will take...

[HUMMERcustoms.com/TAZ]

Do you have pics of the shifter console cover back on to see how the finished job looks inside?

TAZ

[HUMMERcustoms.com/TAZ]

Do you think a Mr. Gasket in line short throw shifter would work on tranny?
This model shifter also has a T handle reverse lock out you pull up on.
Anyone that has run cars on dragstrip gets the idea.

Anyway You may be able to fit shifter right in the factory slot and not make drastic cuts and chnages to factory console I think.

TAZ

[flyin6]

Pretty expensive, but my hat is off to you for a "lead the fleet" in innovation vehicle and project!

[marin8703]

thats pretty good. nice work.

[Agriv8r]

[obzidian]

dudes...

you guys are my hero!!!!!!!!!!!! I was just think how it would be to have my h2 with a 6spd and do dirty power slides and burnouts at will!! The swap looks nice.

question, you mentioned that the 4l80e swap would be "Defeating the purpose.."

could explain why? I hate the 4l65e/60e in such a heavy vehicle. I went through three rebuilds, with the best internals/clutchs/bands/pump vanes, oil porting.... etc... and my 500hp camaro would obliterate the trans in a month or so. First goes 4th/od, then 3rd... then you have nothing!!!!

Anyways, i would like to know more on the 80e swap.

thanks!

[HUMMERcustoms.com/TAZ]

obzidian,
It appears the swap to the 80e required that the tail shaft of 80 e had to be turned down to fit in the swap from 65e so it all match and that just did not help the problem that this guys client was having and that was breaking the tail shafts. So it sounds like could go to tougher tranny but, just weekend the unit by turning down the 80 e to fit so it would still break shafts.

The 80e as you and i agree would be a real way to go.

I'm starting to make my list of parts to get to make this conversion. I will add line lock to this as well. Plus i would like to see what it would take to do a inline drag shifter with lock out reverse and if slot bar of shifter is right it may fit right in the rubber slot already in console. I think it will be just cutting to length to make it all fit. I would appreciate any ideas you have on this and PM me any of the parts for the list i'm coming up with. 2 heads or more are better than one. I'm not going to buy all new because there are enough totaled 3/4 tons out there. So send me some ideas and part numbers from your research or from anyone especially you Rob if you check back on the thread.
Thanks,

TAZ

[randyvettes]

Originally Posted by HUMMERcustoms.com/TAZ

Do you have pics of the shifter console cover back on to see how the finished job looks inside?

TAZ

It turned out PERFECT. I will try to get pics this week. If you didn't know that it was not a factory option, you would never guess that this was a DIY.

[obzidian]

taz:

OK, my understanding that there are a few 80e's around, depending on the year you get one. Generally, you want to pick one up that is newer, e.g., a 2002 versus a pre-2000 80e. There are stronger and the tailshaft is different as well. I will try to get a few part numbers as this stuff doesn't stick in my head!

In my camaro, these are the things that i needed to do the swap. Since this will be for an h2, i can only assume that something will be different, but only time will tell on that.

Anyways, here is a quick list:

*4l80e trans, of course!

*New Driveshaft. If you need to shorten it, you can have you stock driveshaft redone and that is it. Lenghtened, then you need a new one. Mine is hd and can take the 1000rwhp+ i want to throw at it!

*Flexplate. Consider the flexplate as a flywheel of sorts, mine is lighter and stronger than the stock one, you might want to consider it since your into getting this brick moving out! Its from TCI.

*Longer dipstick. This may be application specific but i needed one as the stock trans dipstick wasn't long enough.

*TUNE!!! We are in luck as all we need to do is reflash the stock pcm to have it switched for 4l80e parameters. My camaro is a 98 and i got screwed with that since i cannot reflash it like ours. IT will be exactly the same tables as the 65e is, but now for a 80e.

*Crossmember. Again, application specific but this is the mount for the trans.

*New torque converter. You have to get a new one but now, you can really go for something nice and honestly, it better be a Yank converter or nothing at all. Higher efficiency than any other street converter. Combined with a hight STR, you have a converter that will get rid of the deadspots in acceleration (when you smash the pedal and the trans only kicks up a gear and your at 3500rpm, not two gears down and at 4500rpm)... great converter and you can keep you towing as well.

*Longer cooler lines and possible a new trans cooler. I would do it just to be on the safe side.

*Oh, and a wiring harness that will interface the sensors on the 4l80e with our pcm. Speartech has a one i think. That isn't hard to find or do.

However, you can go with a manual vacum'd 80e. It will shift manually, with no electronics needed so you don't have to reflash the pcm or need a wie harness. It works perfectly using shift/line pressure and some say that it shifts harder/more accurate that the electronic version.

Good luck, if i com up with anything, i'll edit this post. There really isn't a whole lot, but what you need to most is patience and dedication in wanting this to work. Also, some 4l80e came with either a longer or shorter tailshaft, so this maybe what we need to know if we want to do a swap like this.

LaterZ!

[HUMMERcustoms.com/TAZ]

thanks obzidian,

Your info is great. I agree with your choices as they match mine. I would go with the extra tranny cooler.

Yet now I'm thinking about doing the manual tranny and manual transfer exchange. We have a chance to get back into the spring SEMA 2008 GM design and customization contest. We were to be in it spring of 06 and while loading on trailer to head out our custom dash with the 12" touchscreen in it split open. The build was just not strong enough but, Dragon has that solved now and the people told us when were ready again to let them know as they felt bad for us and see that we could get in contest. I as well as Dragon called them asap and told them what happened so they had plenty of time to bring in an alternent for us. Dragon and i were straight up professional with them and all we could do is say we are sorry. They made it feel worse when the guy that was in charge of choosing just the 20 GM rides to be allowed in, said they kept tossing the H2 out and then putting it back in the circle. They were blown away by the Fleetwood Caddy tailights and all the shaving we had done. The guy asked if we were sure we could not make it and this is just 5 days from show and it takes weeks to hand lay that dash design. He said well since you are sure, it had all but been written down on paper that your rig was getting best in show. It was because of all the rides entered you matched allot of old school body work with a hi-tech nerve center then blended them so as to complement each other. It helped us to feel better but, in a way we hurt. We may have gotten there and done nothing.

Because of the 2 year break and updating even more stuff as the sponsors are replacing old stuff we had with the 2008 lines for us to show for them. That is why i feel if I could get a shop to do the manual conversion since we just do not have the time and if the shop is wanting to be known for that it would be well worth their while not counting all the other shows we go to. I know with the tranny conversion that there is most likely 3 to 5 mags that would do stories since they want to do them anyway when Dragon gets all the upgrades done inside. Plus we are going to paint the rig for the 4th time because we have slowly discovered flaws in body work and paint that anyone else but, a good body and paint man would not even come close to finding them but, we are that picky as the judges are also as well as qualified. We like color the scheme we have but, if anyone would go to the pic section and take a look then offer real suggestions on design changes or paint colors it would be considered with strong interest not just OOOHHH that was so nice of you. I have sponsors as the contest is for shops only so sponsors get mention during the deal. I thought about getting someone local for tranny swap or go to the shop that did the one in this thread.

If they wanted to sponsor the conversion and since the spring show is for trucks vans that type of rides no cars and if a shop wanted the national recognition to get the business to do this conversion for owners everywhere, I would find it hard to pass up by allot of H2 owners to get this conversion ffor the gas engines if priced properly in place of going for diesel. It would have allot of traffic and the contest is one of the main events. Rigs sit indoors during the whole SEMA show for all to see until it closes. If the shop that did this for it's customer would be interested we could talk. I have visited with the diesel shop in Kansas briefly before about their conversion and I would think they would like to add this conversion to their line. Anyway with that manual tranny setup in my hi-tech show baby it would blow anything else out of the water that showed up to the 20 on 20 contest as it was called that year i was going.

TAZ