need more power for towing

01_silverado · June 9, 2003

Just wondering the people that do towing with there Silverado 4x4's about extra power. I have a 4.8 ext cab 4x4 and am wanting a little extra power to tow my 3700 lbs travel trailer. At the higher speeds my truck starts climbing with the RPM's and sometimes doesn't switch into the next gear at 60mph @4500-5000.

My truck is completely stock. What should I do?

exhaust, power programmer ??

awdvkd · June 9, 2003

If your within the limits of your truck you can work on your exhaust and air intake. Sounds like a question of how often you tow. If you do it rarely your truck might work, if it is something you do often it sounds like it would be hard on it. I don't know what the gross combined weight of the 4.3 1500 is. That would be the best placed to start. I would definately make sure you had coolers on it.

Ben · June 9, 2003

What is your diff ratio?

What tire size? OEM for 1500 is P rated and must be DERATED min 9% of max weight capacity while keeping at max pressure when towing. If larger than stock dia, effectively reduces diff ratio (smaller numeric).

Lifted? If lifted via suspension, higher U-joint angles, which translates to reduced HP transmitted to pavement.

4.3L engine is just too small to do any real towing. That is most likely married to an econo diff ratio too.

All of the bolt on stuff won't really make the kind of difference you wish...except for blower, but then the longevity of the rig will be in question.

01_silverado · June 9, 2003

I am not sure where you are seeing 4.3 I have a 4.8 in mine.

I have a 3.73 rear with 285/75/16 on an 8" rim for wheel and tire combo and an external tranny cooler installed.

We go out camping twice a month not all to far min 1 1/2 hour drive to our destination.

Will exhaust make a noticeable differance in my truck?

Thanks

Ben · June 9, 2003

I am not sure where you are seeing 4.3 I have a 4.8 in mine.
I have a 3.73 rear with 285/75/16 on an 8" rim for wheel and tire combo and an external tranny cooler installed.

We go out camping twice a month not all to far min 1 1/2 hour drive to our destination.

Will exhaust make a noticeable differance in my truck?

Thanks

Just reading from awdvkd's post...

Stock is LT245/75R16E tires, which are about 30" dia. The LT285/75R16 tires are over 10% larger in dia, which makes your 3.73 diff ratio EFFECTIVELY 3.39's

That is the main reason you have lost power....less diff ratio...more of a empty cruising MPG ratio, not towing ratio.

Still have the 3.73's in the diff pumpkin, but since larger dia tires, they have less rev's per mile driven. So EFFECTIVELY reduced your diff ratio from 3.73's to 3.39's.

The single most effect thing to getting back the power is to either reduce tire dia or change diff gears. Maybe 4.1's which will be closer to the 3.73's..EFFECTIVELY.

PS...your speedometer is also reading slow, by about 10%. Meaning indicates 60mph, but really going 66mph. Same reason, the gearing has EFFECTIVELY been changed by going to larger dia tires.

SilveradoWV · June 9, 2003

I have a 2002 4.8L 4x4 Reg Cab with 3.73s and 265's and I tow 3500lbs up a 7% grade for about 5 miles with no problems at all. I didnt think 285s would make that much difference but something is definately wrong IMO if you are having trouble with 3700lbs. The added weight of an ext cab and the 285s might be the difference between my 02 and yours. I have actually raced a Dodge Ram Indy 500 pace truck edition up this hill when I was pulling 3500lbs and he was empty and the 4.8L killed him, by the time we got to the top he was at my rear bumper. I dont have a tranny cooler on my truck, just however much goes through the radiator. I probably need to get one but oh well 3500lbs probably isnt that much on one but I usually put one on just to help with daily driving. I had it in 2nd gear the whole way up the mountain just about and think the max speed I could do up the 7% grade while loaded was 75-80 mph. The temp gauge didnt go up any and I didnt get a trans too hot message in the message center but I bet that fluid was HOT!! Dont worry, I dont do that all the time just had to smoke that dodge, funny thing is I slowed down to about 55-60 when I got back on top and he never came around me again the whole time????

k1500chevy97 · June 9, 2003

Heres a start ...

Cat back

power programmer

chip

A k&N fipk or **Non-Supporting Vendor** intake

BTW , i towed a 6500lb travel trailer a few times with my 4.3 with no problems what so ever good power but im sure an 8 or diesel would have been better

SilveradoWV · June 9, 2003

Its just that 3700lbs should be no problem for a 4.8 or even a 4.3!

bassdog · June 10, 2003

Are you using tow/haul mode? And are you using D or 3?

I tow an 18ft bass boat that weighs ~ 2500lbs loaded, in "3" with tow/haul mode the tranny does shift on the higher side of the rpm range. At 70 mph I'm at 3K+ rpm and I have 4.11's with stock 245 tires, with the 5.3L.

Your truck should have enough power to tow that trailer easy. The 285's may cause a problem because it is an "extra" load on the drivetrain. If you have the stock tires, try them out and see how it does.

01_silverado · June 11, 2003

When I tow I am in overdrive with the tow/haul button on. I just hate when I have the cruise control on and the truck starts to accelerate to keep it at 60mph the RPM' s just seem to get to high between 4500-5000 and stays there for a while. Is this normal?

silverado3500 · June 11, 2003

Its the 285s, the 285s killed my trucks power with 3.73s and I ended up going to 4.10s. I would urge you to consider a swap to 4.10s. That will put your final drive ratio back close to the 3.73 that your truck came with. The 4.8 has plenty of power to pull a 3700 lb trailer

BDBWTE · June 11, 2003

Heres a start ...

Cat back

power programmer

chip

A k&N fipk or **Non-Supporting Vendor** intake

BTW , i towed a 6500lb travel trailer a few times with my 4.3 with no problems what so ever good power but im sure an 8 or diesel would have been better

I'm with you man the 4.3 is a good motor as is all GM small blocks.. I think people want their trucks to pull the same loaded as unloaded. I pull 15000 on goose with my 6.0 2500HD it slows her down but she pulls it and never has given me problem yet.

For more power I would put in a RV Cam, add exhaust, a little computer tweaking and never forget the power in adding gears.. Put 4.56 gear sets in and let the mechanical leverage do the talking..

bassdog · June 11, 2003

When I tow I am in overdrive with the tow/haul button on. I just hate when I have the cruise control on and the truck starts to accelerate to keep it at 60mph the RPM' s just seem to get to high between 4500-5000 and stays there for a while. Is this normal?

Don't tow in overdrive (D) or cruise unless you are on a long flat stretch of road

Your tranny is shifting too much and those rpm's are high for that period of time. Tow in "3" with tow/haul mode, your gas mileage will suffer a little bit but you'll save your tranny in the long run and you'll have the rpm's closer to where you need them

01_silverado · June 11, 2003

My dealer had told me to drive in overdrive with the tow/haul button on when towing.

Is this correct or not or could this be my problem?

SilveradoWV · June 11, 2003

Thats probably not the problem because it would downshift if it needed. The problem is that downshifting alot causes alot of heat to buildup in the tranny and can cause major problems. Although towing in 3 will make it feel a little better probably!