Hi Folks,
What are your opinions about having tow difficulties on highway. My 2008 H3 3'' lifted on 35'' tires has no power on 4th gear ( and i'm talking about 1200 pounds trailer). I have the same problem with normal tire size. I haven't choice to drive on D3 at 50 mph.


(just to maybe give an idea... my mecanic says that my gaz pump could be change and that's gonna help) plus... I have 11 mpg


Thanks guys to help me

 

How many miles on your vehicle? Could be a number of things from cleaning spark plugs to fluid changes. If you change fuel pump then you should change fuel injectors to allow the flow the pump wants to put out but then a PCM tune might be needed for that change. I've never had a PCM tune done but have read many threads here that suggest it after mods are done.

 

87 000 miles ...

About PCM... Im looking to start some mods as CAI, exaust and which Performance chip or programmer should I buy ?

 

I have towed my trailer with two full size Harley's (roughly 4000lbs) from NJ to FL and back several times. With the A/T you should use D3. Keep it about 65-70 and you should be good. The only mod I have is the Cat back exhaust and a high flow air filter. Gas mileage isn't great but after all it is a 5 cylinder so what do you expect. It is rated for 4500lbs.

 

What is 3" lifted?

I towed a Big Block Chaparral 2330 on dual axle trailer to NE of Detroit from S of Milwaukee (appx 425 miles) which weighs in at #5500. 2007 H3 with Performance (Air Doc Intake, PP TB, PCMofNC.com tune and Efan conversion, MagnaFlow Cat Back exhaust) and Off Road mods (weighs almost 6000# with me in it) on 305 MTZs, tires at 40 PSI cold before I left. Tucked in behind an 18 wheeler 70 MPH in drive the whole way, 65 up big hills (trans kicked down to 3 all by itself) and 75 down the other side. I am sure my MPG was like 10, but that's what a load does. I would not try that with 35s, they kill the I5s power and final drive ratio.



The Manual says "If you have an automatic transmission, you can tow in DRIVE (D). You may want to shift the transmission to THIRD (3) or, if necessary, a lowergear if the transmission shifts too often under heavy loads and/or hilly conditions."

I think that tow in 3rd thing is a carry over belief from the 90s. The tranny is programmed to know when it needs 3 and when it can lock up in 4.