Hey all,
I have a '99 F150 4x4 with a 4.2L and was wondering if anyone has any ideas on how to improve the low end power? It actually does ok on the highway when passing and stuff, it screams and gets movin okay, but when taking off from a standstill it just sucks! I was thinking maybe jumping up to 3.73 gears 'might' help? It also shifts out of overdrive all the time on the highway when going up hills. Any ideas, has anyone else been able to improve these areas of their 4.2L's? And I know already that I should have just gotten the 5.4L, but I needed the 4wd and didn't have the cash, and really didn't want to spend that much on a truck. Any ideas?? Oh, and does anyone know where I can wire an aftermarket tach on this distribitorless ignition??

Thanks,
Scott

 

The 4.2 is really weak on low end power. If you already have 3.55 gears, the 3.73 is a pretty small change. A 4.10 gear would be a nice improvement, but still livable on the highway with standard tires. If you plan on much bigger tires, you might want to consider 4.30 or 4.56 gearing. Research some of the older threads - some of the guys have found ways to do this and save some $ on parts & places to do the labor.

If you have the 3.08 gears now, my condolences. IMO Ford should not even offer this gear with the V-6.

Of all the things you can do short of supercharging, the gears will make the biggest improvement.

A Superchip will help power some down low, but the 4.2 engine will still be rev happy. I love the Superchip because it really improves auto shifting, mileage and power (especially on top) but it will not transform the 4.2 into a torque monster. You will get less shifting out of OD on the highway with the chip because of the better shift programming and more power everywhere.

Maybe you could ask the Superchips guy about a custom program, emphasizing torque? Post in the Ask a Vendor section.

I couldn't feel any difference with the K&N air filter - I think it helps the bigger engines more.

Exhaust options (in front of the cat) are limited on the 4.2, and bigger tubes in back of the cat might not help the low end at all - check the exhaust systems thread.

If you crave low end torque for serious off roading, get an old beater with the big 4.9 liter I-6! Its the exact opposite of the 4.2 - no revs but lots of grunt.

You might also want to consider not spending any more money on the 4.2 and saving it for you next truck with a bigger motor.

Good Luck!



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1999 XLT S/C, 4.2 V-6, auto, 3.55 rear, dark torreador red/harvest gold, bed liner, Sony 10 disc CD, Edelbrock IAS, K&N filter, Superchip

 

Hey, thanks for the advice on the 3.73
gears! I do have the 3.55 right now,
but it looks like the 3.73 will not
make as much of a change as I thought
they would. Another thing is I have
those small tires on my truck right
now. Ford put these little
235/75/16's on a 4wd. Heck, they put
bigger tires on some of their 2wd's.
My next set of tires will probably be
close to the 31x10.50 range, so I am
thinking the 4.10 gears would probably
be ideal since these aren't huge
tires. I think I saw someone post
something about summit gears for
189.00 per set so I may have to check
into that. Anyone know how long of a
job this is? I really haven't looked
at the service manual to see what
kindof a job it is to change these
out. Do you have to pull the axles
out to do this job?

I was thinking about getting a
superchip for the truck, but don't you
have to run premium gas if you do
that? My gas bill on this thing is
high enough, I can't imagine putting
premium in it with gas prices as high
as they are around here right now.

Thanks again,
Scott

 

Hi everyone, I'm one of the unfortunate ones with a 3.08 gear and the V6. I wanted to switch to 3.55 because it would feel like the 3.08 gears with my 265/75R16 tires
instead of my new gear ratio 2.64

I wanted bigger tires for looks and better clearence. And I want to stick to my original ratio because (although not a supertruck) gets me good mpg. My dealer said that it was a 8 hour job.


------------------
1997 XLT 4.2l ORP 5-speed

http://www.eph1fifty.cjb.net

 

Scotty-
You're looking at over $600 for two R&P sets, bearings, install kits, and synthetic fluids. This is assuming that you can install them yourself (I'd recommend letting a pro do it). If you don't get it right, you'll spend more than double trying to get it fixed.

Since you don't want to spend another $3 at the gas pump to get 93 octane required by chips, I'm a little surprised that you'd consider gears. Remember, when you go to higher number gears (like 4.10), your fuel mileage will drop off. Either way -gears or chips- you'll be spending more at the pumps.