enveng427

Ok, so I started a thread a couple of days ago asking if my truck 1997 F150 2WD 4.2 L 3.08 rear could tow a car trailer. Today, I noticed something. The 4.6 has a towing capacity that is 1,000 pounds higher. Normally, that wouldn't shock me or even surprise me. Here's the thing though. The difference between the V6 and V8 engines is all of 3 HP and 10 pound feet of torque. That's within variations on individual engines (not to mention altitude etc). The transmissions and the rear ends should be EXACTLY the same. Not kind of the same. Exactly. Is this just a case of a higher rating to create sales, or am I missing something? I could be missing something like all V8's came with oil coolers for the transmission or the springs are different. Let me know. It's killing me now.

enveng427

To give further info on this, the 4.6 experiences both power and torque at a slightly higher RPM. Meaning that the 4.2 probably has better average power. The V6 engine is also likely to be substantially lighter. I kind of wonder if a cold air intake and new spark plugs isn't all the difference between my V6 and your average V8.

ibd2328

iTrader: (2)

2wd, gear ratio, and transmission.

Jbrew

What year 4.6 ?

enveng427

Thing is, the transmission seems to be exactly the same. 4R70W option code U. They would have rolled down the same assembly line. The rear end gear also is the same. Both trucks are 2WD.

Carcrazygts2

Wrong the gear ratio's maybe the same, but the type of converter is different. A transmission from a modular is completely different from a transmission from a 4.2. The stall and lock up points are different along with the shift pressures being different.

enveng427

1997
4.2 L Essex V6
217 HP at 4800 RPM
262 lb/ft at 3400 RPM

4.6 L Modular V8
220 HP at 4750 or 5000 RPM (depending on who you believe)
265 lb/ft at 4000 RPM

Same 3.08 8.8" rear
Both 2WD

Same 4R70W transmission with the same gear ratios and same strength.

enveng427

Different shift points is a possible explanation. That doesn't, to me at least, explain a 10-15% increase in possible load. The stall speed is integral to the torque converter itself, OReilly auto parts has it being the same part for both trucks. Is it the same part, I don't know. I'd need a Ford part number to be sure.

Jbrew

Here,- I'll fix this, just so your aware. The 4six was , but the your 4two specs were bogus.

4.2 L Essex V6
205 @ 4950 RPM
255 @ 3700 RPM

4.6 L Modular V8
220 @ 4750 RPM
265 @ 4000 RPM

Same 3.08 8.8" rear
Both 2WD

ibd2328

iTrader: (2)

lol