2015 3500 GMC Quigley

[Pinnacle Campers]

I do like the GMC vans better than the Fords. I think the engine choices are better, the exterior/ interior styling is better, ceiling height is higher, dual side doors, and the list goes on.
I only tow in town so don't really need a lot of power making a 5.3 or 6.0 gassers good options.

*I do wish the 4x4 conversion was more DIY friendly.*

Please keep posting, interested to see what you do with the interior layout.

Also post pics of the front suspension if you get a chance.

 

[aod99]

I hear you on the crazy power end of things.

I'm going to keep the tune to more of a tow/econo tune. I am also planning on outfitting it with a dual stage water injection set up. I don't know if it is really needed with the inter-cooler but my PS van sometimes really got the pistons hot climbing long valleys with the trailer, and sometimes even without the trailer. Again, I am going to keep the tuning on it really mild as I don't want to stretch the head studs but I like the idea of greater efficiency from converting the heat in the combustion chamber into power. I figure more power in the higher gears (within reason) will actually be easier on the transmission so it won't be trying to downshift or slip on the big hills. That is, of course, just a rationalization for the course of action that I want to take.

I'd also guess that another reason they're moderately tuned is because of heat in the engine bay. Vans are a tight space after all.

The 6L90 appears to be a pretty beefy trans according to the specs. However, the Duramax can be a beast even with moderate tuning so it wouldn't take much to exceed the tran's torque rating. I'm guessing the van isn't a complete dog in stock form (260HP/525ft-lbs), especially if you're not towing anything???

Don't get me wrong...I'd be lying if I said I wouldn't be turnin' up the juice if I had a Duramax van. I'm just going through the thought process of what breaks when you flash a 900ft-lb tune and go mash on the throttle? My first guess would be you'd roast the torque converter or break some internals (if you had the traction). And come to think of it, is there a large enough market for the Duramax/6L90 combo that aftermarket companies are lining up to build high performance torque converters and billet internals? Parts availability would be something I'd consider.

 

[aod99]

I was able to retro fit slide out towing mirrors on my Ford E350. I guess a few years later Ford starting offering them as an option so a lot of E350s have the slide out tow mirrors.

I can't find anything comparable for the GMC 3500. It doesn't look like pick up mirrors will work because they have a different door angle and all the aftermarket ones I have seen are fix width, ie, you can't slide them in and out depending on if you are towing or not.

The slide out mirrors seem so obviously useful that I figure someone must have made some but I am striking out.

Has anyone with a GMC van had better luck finding slide out tow mirrors?

 

[86cj]

What kind of front suspension did Quigley set it up with?

Congrats on the new GMC very nice indeed, I can't wait to see things come together for you. It's great to see a new GM Quigley on here, the more info on them the better they are one of but a few choices now. I came real close to ordering one and did a fair amount of research here are some pic's for everybody...........

 

[Hazelfilms]

aod99,
do you think you could get a bunch of pics similar to 86cj?? I've also just started looking into a 4x4 conversion for an express 3500, probably a year or two out, but figure I should start researching now... Is your van set up just like the pics above? can you give any info as to if they needed to move anything to make room for the front drive shaft? At this point I'm thinking I'll be going with a solid front axle, but I wanted to try and get an idea if I would need to modify lots of stuff just to fit the drive shaft. Thanks for the post, and as others have said, any extra info on GM van 4x4 conversions is greatly appreciated.

86cj,
are your pics of a 3500, or one of the other modles?
Thanks

 

[simple]

I'd like to see more pics and info compiled concerning GM IFS conversions as well but think this topic deserves its own thread.

Link to thread with info regarding GM IFS conversions.
http://www.expeditionportal.com/forum/threads/137424-GM-IFS-4x4-conversion?p=1754034#post1754034

86cj I reposted your photos over on the new thread.

 

[aod99]

A few updates...

I got EFI programming into the van. It was installed by Maryland Performance Diesel using tunes created by Kory. The van runs much stronger but there are a few glitches in the tune that they are trying to work out. The difference being that the 2015 software is just a tad different. At the moment I don't have cruise control.

We've also got the MBRP stainless 4" pipe installed.

A trip into the West Virginia mountains last weekend, fully loaded inside but no trailer, yielded 19.4 mpg with a lot of switch back mountain climbing and 79mph highway driving.

The GMC build quality has been a little disappointing. The driver's side door has two layers of weather stripping but only one strip makes contact so it had a bad door whistle over 75. I added more from the hardware store and that seems to have quieted it down.

The dog house over the engine does not seem to seal on the passenger side. I get a lot of noise through there and I can feel a gap, even with the cover latches, between the cover and the body of the van. I've ordered some sound deadening material from West Marine to see if I can get that quieted down.

The brakes were great in the mountains, the van handled the curves well and I liked the six speed transmission with the manual gear selection.

I'm still waiting for bumpers, wheels, tires, and some more suspension components.

 

[T.Low]

I was able to retro fit slide out towing mirrors on my Ford E350. I guess a few years later Ford starting offering them as an option so a lot of E350s have the slide out tow mirrors.

I can't find anything comparable for the GMC 3500. It doesn't look like pick up mirrors will work because they have a different door angle and all the aftermarket ones I have seen are fix width, ie, you can't slide them in and out depending on if you are towing or not.

The slide out mirrors seem so obviously useful that I figure someone must have made some but I am striking out.

Has anyone with a GMC van had better luck finding slide out tow mirrors?

I put GM pickup mirrors on my Astro. Just takes some template making. Certainly not a plug n play.

 

[aod99]

Nice mirrors!

Can you share any more details on what you had to do to get them to go? It really looks like you did a nice job to get them integrated to the door lines.

 

[T.Low]

Relatively speaking, yes. Not a perfect integration. It's definitely a bit of function over form, but i stopped sweating these types of details long ago.

Had to replace studs w/ longer ones, drill some new holes, get creative with washers to get mirror/body angle correct. Add more foam backing than the piece included.

For on road, it's eliminated my blind spot. For off road I adjust the bottom mirrors so I can see my tires in relation to ledges, rocks, roots, stumps, etc.

It was well worth an afternoon of monkeying around to replace the tiny stock mirrors.