4.10 gears.

scareylincoln

New member
I have an 04 w/ 130k mi. I'm about to acquire a Lidio tune and am contemplating the Ford racing 4.10's. I commute at least 50mi/day, 6 days/wk mostly highway averaging 80mph. Would I regret the gear change? Wear on the vehicle, mpg's, etc. Thx!
 
With your situation I would get the tune and a CAI only. I got the 4.10s but do not drive mine every day. In the end it is your decision, gas mileage will suffer at 80mph, maybe about 1.5mpg or more.
 
IMO, the car actually runs better with 4.10s at highway speed as you're a tad higher in the power range than you would be with the OEM 3.55s.

I tracked mileage before and after gear installation and saw around 1 mpg difference, but a big improvement in performance.

Your call, but if it were me, I'd do the gears and the tune and never look back.
 
I'd say just do the tune for now. It's such a difference you'll kick yourself for waiting so long. I did the Lidio tune at 100k and 4:10's at 130k. Tune is amazing, 4:10's not so much. Take the gear $'s and treat your Marauder to a professional detail in and out. Much more rewarding and lots of jingle left over.
 
All of the feedback is greatly appreciated! I don't know the maintenance history of the vehicle but it was a former Sherriff's cruiser in N. GA so I'd have to assume it was meticulously maintained. The guys at my shop call it "super clean" especially being a former fleet veh. I've been advised to stay away from the 4.10s not knowing the true maintenance history. I'll assume from all the feedback that the 4.10's are not a cause for concern re: wear and tear on the rest of the drivetrain.
 
All of the feedback is greatly appreciated! I don't know the maintenance history of the vehicle but it was a former Sherriff's cruiser in N. GA so I'd have to assume it was meticulously maintained. The guys at my shop call it "super clean" especially being a former fleet veh. I've been advised to stay away from the 4.10s not knowing the true maintenance history. I'll assume from all the feedback that the 4.10's are not a cause for concern re: wear and tear on the rest of the drivetrain.

4.10s will not harm any other part of the drivetrain. There has been discussion about 4.10s lowering the critical speed of the driveshaft and has caused transmission tail shaft failures above 125mph. That would be the only negative. You will need a tune with the new gears to calibrate the speedometer and shift schedule.
 
The biggest difference I've noticed with the 4.10s mileage-wise is in the city, I don't race on the street, but it's fun to annihilate people off the line, which will lower your mpg. Highway, above 70/75 shouldn't be too wallet impacting, the fun factor tends to make up for that.

If anything, get the tune/CAI first see how you like it then you can get the gears and just update the tune for the speedo/shifting.
 
I love my 4.10's!! I love them more with my supercharger:burnout:


---
- Sent from my iPhone
Eaton Swap + 4.10's = Wreeeeeeeeeedom!!
 
The MM was supposed to have 4.10's from the factory, but they were deleted for CAFE standards. Do you want the car to perform the way it's SUPPOSED to, or just be an EPA slave?
 
%15 less

I have an 04 w/ 130k mi. I'm about to acquire a Lidio tune and am contemplating the Ford racing 4.10's. I commute at least 50mi/day, 6 days/wk mostly highway averaging 80mph. Would I regret the gear change? Wear on the vehicle, mpg's, etc. Thx!

If you average 80mph every day and are concerned about mileage - 3.73's would be small step up and what I'd recommend. At 80 Mph I'm spinning 2500 rpm with 3.73 gears, with 4.10's - 80 is about 2800 rpm. Perhaps try 3.90 ratio - you'll need a tune.

Fact: With 4.10 your engine will get used 15% more for *every* mile, so expect your mileage to be about %15 less. E.g. You'll loose 2-3 mpg.

With 130K, I'd also get new: Carrier (trak-lok) bearing kit, axles - not just the gears.
 
This is a great forum with a lot of interested and knowledgeable members. All of the info is being absorbed and is greatly appreciated. I'm definitely getting the tuner but I'm not sure I want to spend the extra $ on the rear end. Thanks for all the input! Oh, by the way, the 03-04 MM is the best car ever re-created.
 
i drove my car on 1500 mile trip lidio tune 4:10 gears running with traffic got 25mpg on 2 tank fills and 23 mpg on the others. lost mpg when i put the eaton on!! may be my driving!! much more fun to drive now.
 
i drove my car on 1500 mile trip lidio tune 4:10 gears running with traffic got 25mpg on 2 tank fills and 23 mpg on the others. lost mpg when i put the eaton on!! may be my driving!! much more fun to drive now.

Same problem here.

I'm blaming it on the 39 lb injectors and the BAP... ;)
 
If you are running at that speed that much 4.10 gears may not be the best choice for you. It will decrease your MPG and it will increase the wear on the engine as it will turn more revs per mile. With 4.10 gears and that much driving at that speed I'd definitely do the transmission tailshaft bushing pressure lube modification. Here is a good write up with pics. http://www.moddedmustangs.com/forums/99-04/114139-tailshaft-lube-mod-write-up.html or you can buy one already done. This is one of the better I've seen since it includes a braided stainless steel line for plug and play action. http://www.ebay.com/itm/AODE-4R70W-4R75W-Tailshaft-Lube-Mod-Kit-/320646612484?item=320646612484&vxp=mtr Off the top of my head though I'm not sure if the one pictured is the correct length for the Marauder or not. Here is someone that offers both. http://www.blueovalchips.com/index.php?l=product_detail&p=74
http://www.ebay.com/itm/AODE-4R70W-...d-Kit-/320646612484?item=320646612484&vxp=mtr
 
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If you are running at that speed that much 4.10 gears may not be the best choice for you. It will decrease your MPG and it will increase the wear on the engine as it will turn more revs per mile. With 4.10 gears and that much driving at that speed I'd definitely do the transmission tailshaft bushing pressure lube modification. Here is a good write up with pics. http://www.moddedmustangs.com/forums/99-04/114139-tailshaft-lube-mod-write-up.html or you can buy one already done. This is one of the better I've seen since it includes a braided stainless steel line for plug and play action. http://www.ebay.com/itm/AODE-4R70W-...d-Kit-/320646612484?item=320646612484&vxp=mtr
Give me a break!

I've had my 4.10's installed for over 60k miles. Never had a problem with the transmission tailshaft. If you run at over 120MPH for long periods of time I'd definitely do the tail shaft lube mod and get an MMX or carbon fiber driveshaft.

I just ran my Marauder at 80MPH for a total of 4 hours and no problems at all. I do that at least once a month.

As stated previously you'll lose 1-2 MPG and yes the engine will turn 200 - 300 RPMs faster, your not going to wear the motor out.


BTW... the Marauder uses the long tailshaft.
 
Sure I lost MPG's since the 4.10 install. And sure I lost even more MPG's since my Eaton swap(foot to the floor:))

Let's face it. If you want to save gas. By a bicycle.

It's all about SPM's!!!

I get about 1,000 Smiles Per Miles when I drive my MM!!
That's what is all about:burnout:


---
- Sent from my iPhone
Eaton Swap + 4.10's = Wreeeeeeeeeedom!!
 
If you are running at that speed that much 4.10 gears may not be the best choice for you. It will decrease your MPG and it will increase the wear on the engine as it will turn more revs per mile. With 4.10 gears and that much driving at that speed I'd definitely do the transmission tailshaft bushing pressure lube modification. Here is a good write up with pics. http://www.moddedmustangs.com/forums/99-04/114139-tailshaft-lube-mod-write-up.html or you can buy one already done. This is one of the better I've seen since it includes a braided stainless steel line for plug and play action. http://www.ebay.com/itm/AODE-4R70W-...d-Kit-/320646612484?item=320646612484&vxp=mtrOff the top of my head though I'm not sure if the one pictured is the correct length for the Marauder or not. Here is someone that offers both. http://www.blueovalchips.com/index.php?l=product_detail&p=74

I have over 50K miles since I went with 4.10's and never had a issue driving 80+ MPH over 700 miles to MV7 and MV8, plus all my local driving.
 
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