Better Cooling With New Slotted Bumper?

[Hutch65]

I have a 2007 Silverado with the new body style. I will be towing a trailer for the first time this summer and am about to take my truck into the dealership for the installation of the original Chevy trannsmission cooler. I have noticed the slot that appeared in the newer front bumpers and would like to first confirm that it is for cooling, not style. Then I seek an opinion as to whether I could achieve better cooling for towing if I retrofit this bumper section to my truck. Is the sheetmetal behind it the same? Did Chevy go to it to gain better cooling? Can I use it on mine? Would the improvement be enough to justify it?

 

A second towing related question:Does tow mode up the pressure in the transmission of the 2007 4 speed 4.8 auto. I have a small trailer and the set-up has the torque to pull it in overdrive if not climbing too steeply. Would trailer mode lessen the load on my clutches if I didn't need it for the extended range of revs in each gear? I can pull it well at 1100 rpm but tow mode ups that to near 2000, I'll pay the mileage penalty if my clutches need tow mode to gain shift pressure.

[Jsdirt]

I can't answer your questions specifically, but I know the owners manual recommends using tow/haul when hauling 5K lbs. or greater. Below that weight, the shift points become annoyingly high, at least IMHO. I believe the system does increase line pressures ... but I'll let the tranny experts here confirm that for sure.

 

My 1500 has no slot in the bumper itself. I think your referring to the 2500 & up HD models?

[mhenshaw]

The slot it mostly for looks. It came on the 07s with the vmax and then the 09s got it. I wouldn't waste my time getting one put on. No benefit IMO

[Hutch65]

I can't answer your questions specifically, but I know the owners manual recommends using tow/haul when hauling 5K lbs. or greater. Below that weight, the shift points become annoyingly high, at least IMHO. I believe the system does increase line pressures ... but I'll let the tranny experts here confirm that for sure.

 

My 1500 has no slot in the bumper itself. I think your referring to the 2500 & up HD models?

[Hutch65]

I can't answer your questions specifically, but I know the owners manual recommends using tow/haul when hauling 5K lbs. or greater. Below that weight, the shift points become annoyingly high, at least IMHO. I believe the system does increase line pressures ... but I'll let the tranny experts here confirm that for sure.

 

My 1500 has no slot in the bumper itself. I think your referring to the 2500 & up HD models?

 

 

I don't know what year it appeared on the 1500's but I just checked the pictures on the Chevy website and they all have it now.

 

I've tried for awhile now to nail down the line pressure issue and the best I can understand it is some say yes it does and others have said after a certain year, they all had the increase full time so not related to tow/haul on those. So much disagreement on this that I'm still confused. The manual treats tow/haul very vaguely and chevy could do well to give a detailed, technical explanation for those of us who want to know.

[Hutch65]

The slot it mostly for looks. It came on the 07s with the vmax and then the 09s got it. I wouldn't waste my time getting one put on. No benefit IMO

 

 

It's not all that pretty, I still have to wonder if it didn't appear in answer to an underlying cooling issue. The heater in my 2007 heats up really fast and very, very hot. Not complaining about that mind you, fact, I love it! Just thinking this might indicate less outside airflow under the hood.

[Jsdirt]

I've pulled 9,500 lbs. of coal & trailer with my 1500 .... & only on a long, steep hill did the temp gauge barely climb over 210. Was in the spring here in MA, temps in the low 60's.

 

Another time the gauge went over 210 was pulling a 2,000 lb. flatbed trailer with a '89 S10 Blazer on board. Was 95° out. Hill was a 7% grade that went on for at least 4 miles. My old '94 K1500 would've melted down.

[music]

I'd guess, yes... the slot was added for cooling to go with the motor oil cooling added to the 09+ 6L80 trucks with HD tow pkg. Will it benefit the 07 to the point that I'd consider replacing? No. The transmission cooler sits dead center in front of the truck on the 07/08 models... not sure about the 09+. An auxillary cooler should be all you need.

[Stevens03]

I'd guess, yes... the slot was added for cooling to go with the motor oil cooling added to the 09+ 6L80 trucks with HD tow pkg. Will it benefit the 07 to the point that I'd consider replacing? No. The transmission cooler sits dead center in front of the truck on the 07/08 models... not sure about the 09+. An auxillary cooler should be all you need.

 

Agreed. The slot was put there for cooling purposes to allow a little more air flow too

[Hutch65]

I'd guess, yes... the slot was added for cooling to go with the motor oil cooling added to the 09+ 6L80 trucks with HD tow pkg. Will it benefit the 07 to the point that I'd consider replacing? No. The transmission cooler sits dead center in front of the truck on the 07/08 models... not sure about the 09+. An auxillary cooler should be all you need.

 

The slotted bumper was money I don't need to spend, that is good since there is no discressionary spending left in the budget.

Since I don't have the biggest available radiator I am going to install the factory tranny cooler and just watch the digital readout of trans temp and try to adjust if needed. Bigger are available but I like the long pre-shaped hydraulic lines and the cross brace mounting of the cooler bracket On the OEM piece.

 

Still wondering though what years or no years get a line pressure kick from tow/haul mode. If I don't need it to gain shift pressure and protect my clutches, there are times I would run without it just to get a torque converter lockup in overdrive to ride the lower end of my torque curve gently down the road...it's a sweet cruise, gotta look out now and then to realize I'm pulling the 18' trailer.