Rear end gears

[Bill Lalk]

I need some advice on rear gears. I'm just starting to mod up a stock MM, starting with exhaust, CAI, tuner and possible gears. I am not going to 4:11 because most of my driving is highway and I believe in torque rather than low gears. My mechanic buddy recommends 3:73. Is there such a set for the MM? Have any of you put them in and what kind of difference does it make for power, mileage, speedometer and traction control?
Thanks for any advice,
BILL

[yjmud]

go with the 4.10 4v don't have torque anyways
it is only 1/2 a turn more

[SC Cheesehead]

go with the 4.10 4v don't have torque anyways
it is only 1/2 a turn more


^^^^^^^ what he said ^^^^^^

4.10s and a tune will really wake up the car, and definitely will give you the best performance return for your investment.

Keep in mind that 4th gear in the MM transmission is O/D, so at highway speeds the 4.10s will have minimal impact on RPM or gas mileage.

75 mph = 2,400 rpm; this is barely in the cruising range for a 4V 4.6L engine.

I've tracked my mileage since day one, and have seen about a 1/2 mpg drop between the stock gears and the 4.10s. However, my 1/4 times dropped a full second after installation of gears and a DR tune.

[Mr. Man]

What he said^^^^ 3.73 is an option but hardly worth the cost. I'd recommend the 4.10's or stay stock with the 3.55's

[Blackened300a]

I need some advice on rear gears. I'm just starting to mod up a stock MM, starting with exhaust, CAI, tuner and possible gears. I am not going to 4:11 because most of my driving is highway and I believe in torque rather than low gears. My mechanic buddy recommends 3:73. Is there such a set for the MM? Have any of you put them in and what kind of difference does it make for power, mileage, speedometer and traction control?
Thanks for any advice,
BILL

Go 4.10s or else you're just throwing money away for labor and the 3.73 gear set.
Will all my mods, Im still getting over 350 miles to a tank full on the highway.

[Bill Lalk]

If I go with 4:10's and a DR tune, should I still do an exhaust mod? My wife's already warning me against making the car too loud. And we both like the factory sound.
Thoughts?

[ctrlraven]

Adding 4.10 gears and a tune is not going to increase the sound of the car.

[SC Cheesehead]

If I go with 4:10's and a DR tune, should I still do an exhaust mod? My wife's already warning me against making the car too loud. And we both like the factory sound.
Thoughts?


Changing the mufflers or deleting the rear cats will increase the sound level.

As I said in another post, what's the intent of the exhaust mod? If you don't want more noise, but you want more power, look to installing headers, but be prepared to spend some bucks.

Do you have a specific goal for your mods? Are you looking for a big increase in power or do you just want to improve overall responsiveness from stock? Are you looking for 1/4 performance? Is the car going to run consistently at high speeds? Are you planning to stay NA or do you intend to go S/C some time in the future?

Might want to get that all sorted out and then develop a plan to reach your specific targets.

[Bill Lalk]

I am hoping to stay away from too loud. My goal is performance as she's a sled right now. And, yes, someday hope to super charge it.

[ctrlraven]

Just remove the rear pair of cats and leave the rest alone.

[RF Overlord]

I believe in torque rather than low gears. My mechanic buddy recommends 3:73. Torque and low gears have nothing to do with each other.

Your mechanic buddy is likely not used to cars like the Marauder that are heavy, have an engine that is somewhat deficient in torque at low RPM, and have 18" wheels. The difference between the stock 3.55 and 3.73 is not worth the labour and expense.

Those of us who have installed 4.10s can attest to the fact that highway mileage is not significantly impacted.

[SC Cheesehead]

Torque and low gears have nothing to do with each other.

Your mechanic buddy is likely not used to cars like the Marauder that are heavy, have an engine that is somewhat deficient in torque at low RPM, and have 18" wheels. The difference between the stock 3.55 and 3.73 is not worth the labour and expense.

Those of us who have installed 4.10s can attest to the fact that highway mileage is not significantly impacted.

^^^^^^ What RF said ^^^^^^

Unless your buddy's done a lot of work on Marauders, I wouldn't put too much stock in his recommendations.

[Pat]

Bill, go with the 4:10's. The highway mileage is still around 23 with A/C on during the summer.

Exhaust is OK but not worth the expense unless you are into racing. A high speed stall converter, say 3500 RPM, will get you from a standing start to 50 MPH real quick with the 4:10's and still give you great highway mileage.

Regards,

[ctrlraven]

Bill, go with the 4:10's. The highway mileage is still around 23 with A/C on during the summer.

Exhaust is OK but not worth the expense unless you are into racing. A high speed stall converter, say 3500 RPM, will get you from a standing start to 50 MPH real quick with the 4:10's and still give you great highway mileage.

Regards,
If I could go back and get another torque converter I would of gone with a 3000 stall instead of the 3500 only because I now know the relation between stall speed and engine power is what really decides what. Now granted once I finish up all the bolt-ons I think the 3500 would be the right choice. To each their own just depending on what their end goal is with the car.

[SpartaPerformance]

4.10 gears all the way! Need them I got great prices, got a lot of miles I have the install kits too.

[napolitano]

If you put 4:10's on our mm aren't the cars rpm's higher at highway speeds? And wouldn't that wear our engine quicker? I have s/c kit and 3500 stall on mine. I tried to get as close to low end and top end without running high rpm at highway speeds. Am i wrong

[TFB]

4.10 x .68(overdrive) = 2.79 final drive ratio...

Before the overdrive transmissions came on the scene, grandma's LTD generally had 2.75 or 3.00 rears(I'm talking 9" here), so she was pulling as much if not more gear as your Marauder with 4.10s... My '93 Lightning has 4.10 from the factory as did a 3.0L Aerostar I recently junked...

[fastblackmerc]

If you put 4:10's on our mm aren't the cars rpm's higher at highway speeds? And wouldn't that wear our engine quicker? I have s/c kit and 3500 stall on mine. I tried to get as close to low end and top end without running high rpm at highway speeds. Am i wrong

:shake::shake::shake::shake:

Oh please!

Is 200rpm really going to "wear" an engine quicker?

[Blackened300a]

If you put 4:10's on our mm aren't the cars rpm's higher at highway speeds? And wouldn't that wear our engine quicker? I have s/c kit and 3500 stall on mine. I tried to get as close to low end and top end without running high rpm at highway speeds. Am i wrong

Your S/C will put more stress on your engine under boost at WOT then cruising at any RPM will ever do.

[SpartaPerformance]

If you put 4:10's on our mm aren't the cars rpm's higher at highway speeds? And wouldn't that wear our engine quicker? I have s/c kit and 3500 stall on mine. I tried to get as close to low end and top end without running high rpm at highway speeds. Am i wrong

Negative an engine is designed to turn RPM.... that's its function is to create HP. Approx. 500rpm more over factory cruising rpm wont hurt a thing.