I know this has been discussed before, but just looking for general advice. 2010 Hummer H3 Auto with I5 and tow package. Camper has electric brakes so braking isn't a problem. I purchased a Hybrid Camper 19' recently that weighs in at 3500# unloaded. I figure loaded with additional person(s) in vehicle and gear I will be right at 4500#. I knew I would be pushing it, but figured I could do some upgrades. I have already towed with it and it did struggle, but it more or less struggles to stay in Drive at 65-70mph which is what I'm looking to do. Getting up to speed was actually alright. I need to put new plugs in which I think will help as they have 70k on them now. Also, what is a safe RPM range if cruising in 3rd?

1) I for sure plan to get a pcmforless tune optimized for towing and premium 93 fuel. Depending on other items below could be optimized for those too. But I need to make a decision on below items before I get the tune.
2) I was thinking about an efan, but don't think I like the efan kit from pcmforless as I heard it is loud. There is another efan kit that can be found on 355nation which is a canyon/colorado forum. The supermodulation kit has some good/rave reviews. I'm checking with him on whether it is available for the H3 which it was at one time, but not sure anymore.
3) Maybe an exhaust. A few options, but the Gibson single exhaust can be found on summit racing for about $380. Is the whole cat back exhaust worth it or could I just stick a different muffler(higher flow) and get similar performance gains? Is there any value in a single inlet dual exhaust which is about $500. I know I could go Magnaflow, but those are real pricey. I don't want loud or drone either. Slightly throaty would be OK.
4) I could do an airdoc or K&N cold air intake, but have heard that exhaust is more worth it.

Any advice would be appreciated. Thanks

 

70 mph is to fast to tow a trailer worked for u haul 29 years there speed limlt was 55 mph

 

I'm sure there are opinions on max mph towing a trailer and yes I understand that U-Hauls is 55. Have you ever driven through the Freeways in and throughout Chicago. In my opinion if you are doing 55 while everybody else is doing 80, that's just straight up dangerous.

I worked for a company that did nothing but tow trailers from 20-35' footers and they always did 70-75, 5 crews, week in and week out, and they never had a problem and they were doing it that way for 30 years.

Have you ever seen the transport trucks moving these campers all over the country from the mfg to the dealers? Those guys are certainly not doing 55.

I respect your opinion and Uhaul has there policy I guess. In addition, Uhauls customers usually have zero experience pulling trailers. Besides Uhaul makes more money if there customers drive slower.

 

Just trying to help, i use to tow my humvee at 70 mph with my 96 h1. I put a chip in my h3, took off muffler, got rid of air box, get rid of fan, replaced with elect. Does have more power and 3 mooe mpg. Also lowered iot 2 inches. I towed a m38 jeep from mid maryland to south carolina, had plenty of power. What does your trailer weiight ?

 

Do either of you use helper bags in the rear to level only under load? Looking for reviews / thoughts. Thanks

 

I honestly think you are asking way to much out of your h3.This was never made to be a trailer towing machine. Not that it cannot do it but your transmission and driveline are going to take a beating and will head south real soon with that much weight behind you.
The tow rating that is published it rated at ideal conditions and we all know that those conditions just do not exist. I have a 23 foot 3880 pound camper that weighs around 4600 loaded and tow with a 4x4 silverado with 5.3 and i can personally tell you that is the most i would care to tow. We do go to hilly west virginia and the motor is screaming going into the hills.
Let your hummer tackle the road and find a cheap tow option that can safely get you there, just my two cents.

 

The H3 has leaf springs and must say they are decent. My trailer tongue weight is only 350# also, but I do have a weight distribution hitch to help. I can say with my trailer hooked up the H3 sits almost perfectly level. It actually takes the rake out of the H3 that a lot of guys try to take out anyway.

I agree about towing, but I'm stuck with it. My problem is, I bought my camper with what I thought was a 3000# unloaded weight. I later found out that the weight sticker on my trailer was wrong and it's actually 3500#. My plans were to do some upgrades anyway to deal with the 3000# weight, but it turned out I was even more beyond what I felt comfortable with. But I'm stuck with it. My problem is, I need a SUV and getting anything that I trust I would have to trade in my H3 which I really don't want to do.

I have done an airdoc with AEM filter, ported throttle body, super sparkz kit, new plugs, and a absolute dialed in tune from supermodulation. He not only worked on the PCM, but also the TCM. Anything over 1800RPM's is performance mode and it's tuned for 93 octane. It made a drastic improvement over stock and completely woke up the H3. I improved my gas mileage from 16 mixed to 19mpg.

 

I'll continue the towing advise issue... I've got a 2007 Hummer H3 I5 and just purchased a Jayco Feather Travel Trailer. It's 3000Lb dry and I would appreciate all tips and tricks for city and highway travel.
Thanks, E