I have an 06 F350 long bed SRW. 6.0 4x4 3.73 rear end auto Factory 20" wheels and 275-65-20 at 34.20 inches tall. I have done the BPD kit w/external oil cooler and head studs. The truck has been gone through. fluids shocks, rotors, upper lower Ball joints ect. I have an SCT and an edge cts. Just upgraded the BPD external oil cooler to the larger one, as I have been having heating issues when towing in PHX going to the mountains. In the summer the temps will be 110 and 7% grades getting into the mountains. pulling a FW toy hauler 17,000 lbs. The motor heats up can't do much more than 35-40 mph. or it will over heat. The old oil cooler was too small the oil temp would push 260 even w/the ect at 230 or lower so I would get the wrench warning on the dash for the temp differential. I have since changed the oil cooler to the larger one and it helped. I checked my gear ratio w the larger factory tire package. It is now the same as a 3.42. I was told to change my gearing to a 4.10 or a 4.30. The 4.10 would raise the rpm by about 250 rpm going to a 4.30 would be and extra 400 rpm. They say these will lower the engine temps by reducing the stress on the drive train.

Does anyone have experience with these ratios and if they would help the engine heat and speed going up the hills?

also running the SCT tow tune included w/the programmer so about 50hp and 50 lbs of TQ. the tow tune has a fan mod added to engage the fan 10 degrees sooner and this also helps w both ect and eot.

Also cant seem to get on the motor too much as the EGT's go over 1300 pretty quick.

Thanks

 

I don't think you'll see an improvement that would justify the cost of changing to 4.30's. I ran an 06 F350 dually long bed 6.0 stock with 4:30's towing a 19,000 lb fiver and found had the same heat concerns and even lower speeds on the hills. The 4.30's might be easier on the engine, but in the end, the amount of work required to tow 17,000 lbs up a 7% grade remains the same.
The 4.30's will raise the rpm by 400 as you stated, but probably will force a downshift to the next lower gear as you hit the top end.

 

When doing the 35 to 40 have you manually dropped the gears? That was the secret on my 05 and the temps would drop dramatically. Don't wait for it to downshift on it's own.

 

Yes I drop it into 3rd. How much weight were you towing and do you know what gears you were running?

Thanks

 

I had a 450 with 4.30 gears and had the same problem towing a 18000 lbs toy hauler. I had the same issues. Gearing will not help you, it's not worth it. You are pretty much where you are.

 

3.73's and app. 15k. That's in the Eastern Sierras with 7 to 8 degree grades.

 

keep working on removing heat.....

what about water sprayers to the coolers.. and radiator...

larger radiator... as in aftermarket..

what about alcohol injection ? it should cool the incoming air to the engine.

 

Brother in law lives in Tucson. He added a electric fan to the radiator and an aux fan and cooler for the trans. Seemed to help him.


My suggestion would be going to a 18" rim/tire combo and that is about all you can do.


If you could put a bigger radiator on it that would help but there is no more room.


Have you checked to make sure your shroud is 100% complete. Also I take it the clutch fan is working properly? When pull that hard do you hear the clutch fan kick on high and hear the airplane under the hood?

 

BPD Water pump?

 

I did not realize the 6.0 had cooling problems towing heavy. I think I have read that the EGR delete helps with this as well? I have no idea if it's true, but I am curious to see what could help resolve this. I have been considering a 6.0 for a little while now. I probably won't tow with it though as I have the truck in my sig that does that job pretty well.

 

The truck does get worm but the oil temp is the big problem. If I put a better radiator in the differential between the oil and coolant will be too big and i will get the wrench warning on the dash. I have put the larger BPD external oil cooler on but the oil temp still runs in the 140's and if I push it into the 150's. So a bigger radiator will give me a warning and make the motor de rate or run in limp mode.

I have been looking into gearing. My truck with 3.73 and the factory 20 option gives me a 3.48 effective gear ratio. I found a great app online to calculate this. Just google tire size and gear ratio. I know this is too low for towing the weight I am. To get back to a 3.73 I would need to put in a 4.10. If I put a 4.30 in my effective ratio would be a 4.04. I checked my rpm today at 75mph it was 2,000 so if I went to 4.30 I would be at 2,400 to 2,500 rpm. I know either a 4.10 or 4.30 would ease the stress on the motor just don't know which to go with. I would guess both would reduce temps just don't know how much.

 

In looking up your trucks towing capacity. Assuming crew cab. 15500 is max tow weight. So you are really loading heavy.
The weight you listed. Is that the loaded weight? People, toys , food etc.

 

No But the people who rebuilt my motor said the stock one was good.

 

Loaded its supposed to be 16,500 but I estimated a little high because every RV I have had has weighed more that the stated weight.

Thanks

 

I'm not that familiar with the 6.0 but to me it really sounds like you should consider upgrading / replacing your water pump. The bulk of the heat will not be removed if you have a suspect pump... This is true of any motor.