Top speed with 4.10s?

[Advancedautosec]

Anyone know the top possible speed if i install 4.10s? i was told it would keep me under 110mph. I dont think i plan on going that fast anyway but just curious. Also someone told me that my MM could develop a whine if i do the 4.10s.

[sabtaj1]

I have 4.10's and lets just say with the speedo reading its last number the tach is reading 5000.

[Advancedautosec]

you know if that would void my warranty?

[fastblackmerc]

The only whine that may develope is from your passenger / wife/ GF or others in the car. I've hit 120-130 for a few seconds with no harm done. To sustain those speeds and higher you should either get the stock driveshaft balanced or install an afermarkhet one and do the forced tailshaft lube mod.

[FordNut]

If the rest of the driveline is upgraded...

Before my supercharger I saw 145 and still climbing with the 4.10's Who knows what it would do now.

[fastblackmerc]

you know if that would void my warranty?

How would it void the warranty? Is this the first car you've owned? There is no way for anyone to tell how fast the car has gone unless they were sitting in the car when it happened...

[Advancedautosec]

i was talking about the gears...

[sailsmen]

Just balancing will not cure the problem.

The cars are speed limtd due to the DS. At speed it whips resulting in vibration and tearing out the trans output.

Purchasing a stiffer DS enables a higher speed before it begins to whip.

[fastblackmerc]

i was talking about the gears...

Sorry.

No one will know unless they happen to see something stamped on the gears or they decide to count the gears and figure out that they are 4.10's and not 3.55's. Purchase the FMS 4.10's and ask your local dealership to install them. They are Ford parts so it shouldn't be a problem.

[Advancedautosec]

no prob. thats my next move then, 4.10s and magnaflow exhaust. so far all i did was predator programer and k&n intake. tryin to catch up to u guys!

[Herco23]

Deciding for 4.10 was very difficult for me but now that I have them, I enjoy every second of it.

[FordNut]

Warranty is funny, depends on the dealer sort of. The only way to use the 4.10 gears is with a chip or PCM flash. Technically that voids the powertrain warranty.

[Bradley G]

My friend tells me a funny story, about the time I lost my motor.10/'05
A Marauder gets towed in to a local L/M store purchased used W/ 88 tics,It was under ESP,the service writer goes in the glove box, for the warranty papers and the glove box had a pile of time slips in it.:banana:
Naw, it won't void the warranty :argue: J/K

[Advancedautosec]

does changing to the 4.10s effect highway driving speeds? for example constantly driving at 80 mph, what rpm range am i lookin at? I've been told so many different things from different sources.

[Daily 03]

With 4:10's at 80 MPH I am turning about 2800 RPM.

[99SVT]

I just installed 4:10's, well worth it. Drivability is much better and highway RPMs are nothing that that will hurt the motor or gas mileage excessively.

Also, if you have a predator check to see if you can change the gear calibration yourself first (it'll be in the axle ratio menu). Some units aren't compatible with the Marauder for end user adjustability, but a dynotuner or vendor should be able to adjust it easily.

[fastduo]

To sustain those speeds and higher you should either get the stock driveshaft balanced or install an afermarkhet one and do the forced tailshaft lube mod.

Newbe explanation needed: What is the forced tailshaft lube mod?

[fastblackmerc]

Newbe explanation needed: What is the forced tailshaft lube mod?
The search button is your friend.

[fastblackmerc]

Installing 4.10's will increase your RPM's by about 200 and you'll lose 1 - 2mpg.

[MM03MOK]

Newbe explanation needed: What is the forced tailshaft lube mod?
http://www.mercurymarauder.net/forums/showthread.php?t=30984

[magindat]

Top speed will vary based on several conditions

Download this excel spreadsheet and input your own rear gear and revs/mile for tires and start calcutatin. Tranny gear ratios are already there.

http://www.magindat.net/ssm/info/4r70wratios.xls

[JonW]

You should be able to hit 140 mph with 4.10s. I had mine to 125 in 3rd gear, and backed down. I had driveshaft fears, and the back end was starting to feel light.