[whiplash2]

I am new to this and am trying to figure out how to make truck cruise at 70mph easier. I have 410's. How hard and how expensive would it be to switch to 355's? I have 33's on truck and I know I could raise front and put 35's on but my wife thinks it's to tall already. Any ideas? /ubbthreads/images/graemlins/shrug.gif

 

[DieselWiezil]

welcome to the club!!! I am gonna change mine out as soon as I get out of school to 3L55!!!

 

[RodsPwrStroke]

Whiplash2,

I have 4:10s and 35s on mine and no change buddy, I think the only thing to do is gears. But if you find another way let me know.

 

[DieselWiezil]

try a junkyard and find a axle, useually you can pic them up for 200-300 bucks, last i checked the gear swap was 400+ if you pay somone to do it!

 

[larrgh]

Might want to look in the 9" Ford solid pinion spacer. It doesn't require all the high torque to initially crush the crush spacer.

BTW...the 10.25 rear end uses the 9" Ford Pinion crush spacer between the bearings.

 

[lukecline]

Easy!!! I had a buddy with a 3/4 ton 4x4 that had 3.55's AND he wanted my 4.10's. We ended up swapping complete rear axles and pumpkins in the front. One full day later i had the oh so wonderful 3.55's and boy am i loven em. With 410s at 80 mph i was turning 2600 rpms, now i turn ~2200 rpms, soooo much quieter on the hwy. I would do some lookin around and maybe you can find a deal like the one i found.

later, luke

 

[GSXRTURBOQUAD]

Lucky you! I actually purchased a Gear Vender, but I might just sell it and do a gear change as well(still trying to decide). /ubbthreads/images/graemlins/shrug.gif

 

[AlanB]

I should have my 3.55's in a few days, I would look in a salvage yard ( thanks RSP ). TomS did some looking for me while I was out of town and was unable to find a new gear set for a Dana 50 front end.


Later

AlanB

 

[rckcrlr]

First 35's will only raise the truck 1 inch (2 inchs in diameter equals 1 inch in radius)

Second, new gears are not to bad. Try Six States Dist, or Randys Ring and Pinion. Stay away from Genuine gear, their gears are terrible!!
Setting up gears is not that difficult, but does require some special tools. If you have not done it, and don't have someone around to help that has done it, probably best to take it to someone.
Unless you truck has very low miles, I would do new bearings to, especially on the rear! Probably about $125 for a bearing kit.
You will need new carriers for frt/rear. I assume yours is a 350?
If not you may be able to find a TTB 50 drop in in a wrecking yard....but I would definately go new in the rear....It is some times difficult to get used gears to set up in a different housing....Somtimes the will whine.

HTH
Marc

 

[TravisT]

I'd advertise here. I know a guy who traded his 3.55s for 4.10s recently so customers are out there. Personally I love the 3.55s. I can cruise with the spedo buried but it sure sucks the juice. The only bad thing is that I now have 35s and it REALLY hurt my mileage. I used to be getting 19.5 all day long on the big road, but now I'm lucky to get 16. So now I'm wondering what 4.10s would feel like. Plus with 35s and 3.55s my truck is much slower. What I would like is 4.10s and 37s. I think that would be a nice combo.

 

[TravisT]

On the dyno, would there be any output differences between the 3.55s and the 4.10s? anyone have any hard data to support that?

 

[richmondfarms]

My guess is 3.55's would dyno less torque, but horsepower should be close to the same. Has anyone on this thread thought about 3.73's??

 

[gnxtc2]

There is no horsepower difference between gears. Gears move your hp/tq range. It doesn't matter to the dyno if you have taller tires or gears.

When you which into 4L, did you gain horsepower /ubbthreads/images/graemlins/rolleyes.gif /ubbthreads/images/graemlins/shrug.gif, no, just moved the power range.

I have 3.55s and love them. Probably the ideal ratio is 3.73s, like the SD

Billy T.
[email protected]

 

[davideoftex]

I have the 3:55's and would like to have the 4:10's.
David /ubbthreads/images/graemlins/rolleyes.gif /ubbthreads/images/graemlins/biggrin.gif /ubbthreads/images/graemlins/rolleyes.gif

 

[97Strokerman]

Now why would you do that when you can have the best of both.That Gear Vendor is probably the best mod I put on my truck, except maybe stage 1's. I have the towing power and low end of the 4.10, and the hiway cruisin with the Gv. I can cruise about 80 mph in double Od @ 2000 rpm and have lots of pedal to spare, and good fuel mileage to boot. Do yourself a favor and put that GV in..............Dave

 

[ISTOCK51]

"I have the 3:55's and would like to have the 4:10's."
Well I have the 4:10s and would like to have the 3:55s.
I am in Austin, Texas. Is your truck 4x4 or 4x2?
Mine is 4x2. You can take a ride in my truck (and vice versa) and be assured the gears are totally silent. We could swap rears in an afternoon at my shop.

Let me know!

 

[agsF2501]

I would be willing to take you up on that deal if no one else does. Are you talking gears, or rear-ends??

ART

 

[davideoftex]

I am willing but I need front and back. /ubbthreads/images/graemlins/rolleyes.gif I would think it would have to be whole axles. /ubbthreads/images/graemlins/shrug.gif

 

[ISTOCK51]

Whole axles. Maybe remove brakes and we each keep our original brakes
Way too much work to set up gears.
I don't have front. No 4x2s out there?
Art you have a 4x4, correct?

 

[TimC63]

[ QUOTE ]
There is no horsepower difference between gears. Gears move your hp/tq range. It doesn't matter to the dyno if you have taller tires or gears.

When you which into 4L, did you gain horsepower , no, just moved the power range.

I have 3.55s and love them. Probably the ideal ratio is 3.73s, like the SD

[/ QUOTE ]

I agreed with gnxtc2.

Remember horsepower is "work/time." The Work calculation includes DISTANCE that the force is applied over. So when a truck with 4:10's accelerates the rollers up in less time it is also doing less work (fewer roller revs) so the "advantage" factors out in the calculation. Or, the difference distance and time factor each other out. The real-life towing advantage is not factored out but the horsepower numbers aren't affected.

I have also given a lot of thought to gears as towing with 3:55's and 265/75's is a little less than ideal but works nice when unloaded. I came to the same conclusion, 3:73 would probably be "just right."

My $0.02

God Bless,

TC

***I am not an engineer and I do not play one on TV, but I took physics in college once (or was that twice?).