3.73LS vs 4.30LS

Fords For Ever · #1 (**permalink**) 03-04-2002, 11:03 PM

Looking for a used CC 4x4 V-10 for general use (light towing to 3,000lbs, and winter off road/elk hunting) and live at 7,000 ft elv. It appears that the 3.73 was not offered as limited slip in 2000 but the 4.30 was. I have tried to build this truck on vehix.com but it somehow defaults to a diesel when I ad a AT and limited slip. I have all the Ford brouchures since 1999 but they are not clear on the options and the salemen don't know historic details. Others on this site talk about 3.73LS in 2002 models but is that the first year for those gears in a V-10 w/AT? By the way, after reading other posts, it appears that the 3.73 does get better mileage and you probably do not need the 4.30 if you don't tow really heavy loads. Any help?

Sportdeck262 · #2 (**permalink**) 03-04-2002, 11:52 PM

I can't help with what year/model the LS3.73 was available, but I can give you some of my experiences with my Ex. I've got a 2000 Ex with V10 and 3.73 rearend. I don't/can't remember if it is a LS or not. I frequently tow over 7K without a problem. I like to keep the RPMs around 2200-2500 to maximize torque. The only problem with the 3.73 is at this rpm range your going 70-75MPH in OD which may not be the speed you want to tow at. When I lockout OD, it jumps to 3000 rpm to maintain 60MPH in 3rd. Without doing the math, with the 4.30s your OD towing speed in the power band will probably be in the 60-65MPH range. But if you're only towing 3000 lbs, you won't have a problem with a lack or torque or horsepower at any speed/rpm combination with the 3.73s.

You won't be disapointed when you pick out the truck you want.

Enjoy

Monsta · #3 (**permalink**) 03-05-2002, 07:55 AM

Concensus is that the difference in MPG is about +1-2 for the 3.73's & the stock LS unit is not very good.

So no matter what year it became available (I still don't know that answer) for the 3.73's, you're better off getting a good aftermarket unit. Although, there are reports of AMSoil gear oil being used in the rear-end of these trucks with LS units with some really good results.

I believe NoMo will know the answer about what year it was available. Wait here...he'll be along...

MKJRH 00 · #4 (**permalink**) 03-05-2002, 08:30 AM

I have a 2000 F-350, 4x4, V-10, SC with 3.73 gears and limited slip. The truck has not been put to the test so I can't verify the usefulness of the LS, but I have had no problems. My mileage runs around 13.8 highway and around 13 for general use (combined).

Just an observation, we also own a 97 Exedition with the 4.6L V-8 and it struggles to hold overdrive on interstate hills of any significance. The V-10 can make the same drive (Central Ohio to Pittsburgh area) and never even act like it wants to shift.

Fords For Ever · #5 (**permalink**) 03-05-2002, 10:10 AM

Thanks for all the info. From what you guys have said, for my application, the LS3.73 would be the best choice. Too bad to hear they don't operate very well but I will make a not of the oil change.:-)

3992824 · #6 (**permalink**) 03-05-2002, 10:33 PM

3.73LS became available the on the 6.8L Excursion (roughly) March of 2000. That's when I ordered mine. It was a late availability option, as was the reverse sensing option. I believe the 3.73LS was available before then on the PSD Exc. and the Super Duty's.

I went back and forth between the 4.30 and the 3.73 before I ordered, and finally chose the 3.73(LS) I wish I'd ordered the 4.30! We tow a 31 ft Holiday Rambler 3-4K a year, and at 65 mph, it won't hold OD unless it's absolutely flat with no headwind! 3rd gear runs about 2800 at 65 mph while towing. A little bit on the high rpm side, but it runs strong up most hills without lagging!

I don't think the difference in mileage between the two could amount to more than 1 mpg and I believe Ford knew what they were doing by offering the 4.30 for towing.

ribbs · #7 (**permalink**) 03-08-2002, 08:17 PM

i have a 2000 v10 with 4.73 ls. the 3.70 with ls was not available in california due to emissions control. if you wanted ls you had to get a 4.73 rearend in calif. gas mileage is 13 and 10 when i tow a 10000lb 5th wheel. hope that helps

ribbs · #8 (**permalink**) 03-08-2002, 08:19 PM

check those numbers. i have a 4.30 with ls and the 3.73 with ls was not available in calif. sorry

Outpost22 · #9 (**permalink**) 03-09-2002, 12:16 AM

Interesting. I have a CA emmisions equipped truck (sold in Oregon) w/ 3.73 LS, V10, 2000 model year. Maybe you just can't BUY them in CA this way, but they are built. So go to Oregon and drive it back if you want one

Edmo · #10 (**permalink**) 03-09-2002, 02:55 PM

>...the stock LS unit is not very good.

Monsta,

The 4.30 Limited Slip in my Super Duty must have been put together on a good day...

My truck (2001 F-250 Crew Cab 4x4 long box) does really well on the icy streets of Anchorage without having to drop it into 4 wheel drive that often. This is compared to a friend of mine with the same truck minus the LS who has to run in 4 wheel drive just to get moving.

Maybe not the best LS system, but it works for me...

Edmo

Truck Man · #11 (**permalink**) 03-09-2002, 07:06 PM

>Looking for a used CC 4x4 V-10 for general use (light towing
>to 3,000lbs, and winter off road/elk hunting) and live at
>7,000 ft elv. It appears that the 3.73 was not offered as
>limited slip in 2000 but the 4.30 was. I have tried to
>build this truck on vehix.com but it somehow defaults to a
>diesel when I ad a AT and limited slip. I have all the Ford
>brouchures since 1999 but they are not clear on the options
>and the salemen don't know historic details. Others on this
>site talk about 3.73LS in 2002 models but is that the first
>year for those gears in a V-10 w/AT? By the way, after
>reading other posts, it appears that the 3.73 does get
>better mileage and you probably do not need the 4.30 if you
>don't tow really heavy loads. Any help?

I have a '99 F-250SD, Regular Cab, V-10, A/T, 3.73, 2WD.

I can tell you that back in '99 if you wanted a truck like mine, with V-10, Auto, 3.73 axle, limited slip was not available. Only 4.30 had it and I didn't need that as much as I wanted a LS axle.

I get around 14-15 mpg with no load, in typical road driving. Easy 15 if I can hold speed continuous around 70 on Interstates.

You can't get that with the extra weight and drag of 4X4 hardware. Expect at least 3-5 MPG loss, from what I'v heard.

69_bronco · #12 (**permalink**) 03-09-2002, 10:11 PM

I ordered my 2000 F-250 CC 2WD AT with 3.73LS (California emissions). Mine had a Sept build date. After the dealer dropped it of the lift, I ordered the exact same truck,only a 2001 with 4.30LS. I was told, and I looked at their order book, that the 3.73LS wasn't offered with the V-10 auto in 01. I haven't noticed any real difference in the milage, and it only runs about 200 rpms higher than the other truck. All in all, I'm happier with the 4.30s for pulling my fiver.It only tachs at about 2800 @ 70mph.

docsilva · #13 (**permalink**) 03-20-2002, 07:52 PM

2002 F350 reg cab V10 4.30. First 200 miles 11.1 mpg. Second fill up (301 miles) 12.8 mpg. Mixed city and highway.
Anyone know the rpm at 65 in V10 with 3.73. Mine is 2100 at 65, 2250 at 70.

Monsta · #14 (**permalink**) 03-20-2002, 08:20 PM

>2002 F350 reg cab V10 4.30. First 200 miles 11.1 mpg.
>Second fill up (301 miles) 12.8 mpg. Mixed city and
>highway.
>Anyone know the rpm at 65 in V10 with 3.73. Mine is 2100 at
>65, 2250 at 70.

Well, 68mph is 2000rpm with my 3.73's.

Hankery · #15 (**permalink**) 03-22-2002, 06:03 PM

[updated:LAST EDITED ON 22-Mar-02 AT 06:08*PM (EST)]I bought mine in Calif, 05/2001 It is a superduty extended cab.
V-10, 3:73 ls rear end. I pull a 10500lb 5th wheel just fine.
I don`t know how the little face got there. (3:73 LS)