3.55 mpg vs 4.10 mpg with 33" or 35" tires - Diesel Forum

black_smoke6.9 · 03-22-2005, 03:49 PM

As a couple of my previous posts have said I am rebuilding a D60 for the front of my truck. I currently have 3.55 gears with 33" tires. I would like to have some 3.73 gears but was told my drivetrain warehouse that they do not make them for a d60 reverse cut. So I am stuck between keeping the 3.55 or getting 4:10. Later I plan to go to 35" tires. I like the 3.55 but don't know how they would do with 35" tires being that I pull every know and then and when I do it is a pretty heavy load. I curently get bewtween 16 and 18 mpg now unloaded. I was just wondering how bad the 4.10's would hurt my fuel mileage. Let me hear what you guys think about the different gear ratios and tire size combos. Thanks

RonKZ650 · 03-22-2005, 04:26 PM

I don't know, but I'm glad I misunderstood your question. I thought you were now getting 4.10mpg and were getting 3.55mpg. Glad that's not the case, but if it were I guess 4.10 would be a 20% "better" number than 3.55. [img]/ubbthreads/images/graemlins/laugh.gif[/img]
[ QUOTE ]
As a couple of my previous posts have said I am rebuilding a D60 for the front of my truck. I currently have 3.55 gears with 33" tires. I would like to have some 3.73 gears but was told my drivetrain warehouse that they do not make them for a d60 reverse cut. So I am stuck between keeping the 3.55 or getting 4:10. Later I plan to go to 35" tires. I like the 3.55 but don't know how they would do with 35" tires being that I pull every know and then and when I do it is a pretty heavy load. I curently get bewtween 16 and 18 mpg now unloaded. I was just wondering how bad the 4.10's would hurt my fuel mileage. Let me hear what you guys think about the different gear ratios and tire size combos. Thanks

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roxndirt64 · 03-22-2005, 04:28 PM

My 88' has 3.55s and my 97' has 4.10s. I prefere the 3.55s. You can always run the small tires when you know you are going to pull heavy and run the 35s the rest of the time.

black_smoke6.9 · 03-22-2005, 04:34 PM

I never thought about that one I guess I will have to hang on to those stock aluminum wheels plus I already have two brand new 285 70 mounted on two of them. Don't really want to change the wheels out every time I pull something but I am pulling something a long distance it would be a good idea.

mike96 · 03-22-2005, 04:46 PM

i have 4.10 gears and 35" tires (4x4) and get between 14 and 16 (in town)depending on how i drive,on the highway empty i would say 18 , i didn't notice a difference when i went from 285's to the 35's if there was it wasn't much

mike96 · 03-22-2005, 04:48 PM

i just saw you have the cali kit for thr fpr how do you like it ,was it hard to install? what kind of pressure did it bump you up to?

beretzs · 03-22-2005, 05:03 PM

It seems like you would be around your goal of 3.73's with the 35's and 4.10's. Not sure, but you can always pull up a gear calculator and do the math. As for not making reverse cut gears for the D60? That is horsecrap. That is the most popular axle available, next to a D44, you can get them, check out Randy's Ring and Pinion, or any other off road shop. They are out there. Scotty

Quadzilla · 03-22-2005, 05:05 PM

I've got 35" tires and a 4.10 rear end. I get up to 20mpg on the freeway at 70mph. I would think that 3.55's and 35" tires would make it awfully long legged for towing. Swapping out the wheels when you tow is a great idea, should you choose to go with the 3.55's.

Stymie · 03-22-2005, 06:02 PM

who ever you spoke with about the lack of 3.73's is a moron, and i wouldnt give him any money.
Try here

Stymie · 03-22-2005, 06:02 PM

Post deleted by Dusten

black_smoke6.9 · 03-22-2005, 06:16 PM

[ QUOTE ]
It seems like you would be around your goal of 3.73's with the 35's and 4.10's. Not sure, but you can always pull up a gear calculator and do the math. As for not making reverse cut gears for the D60? That is horsecrap. That is the most popular axle available, next to a D44, you can get them, check out Randy's Ring and Pinion, or any other off road shop. They are out there. Scotty

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Drivetrain warehouse told me that there were 3.73's for the d50 but not for d60.

I am kind of leaning toward sticking with the 3.55's for now they work pretty good for me know with 33's but not to sure about them with 35's. The main reason I am insterested in the 4.10's is because it is only $200 more for front and rear with everthing needed to install rather than just installing 3.55's in front with everything needed to install. Just don't want to take a big chunck out of my fuel milage with 4:10's due to fuel prices now days. The 4.10's with 35's would bring me about back to where my actual gear ratio is now.

I have been using the crap out of this gear calcualtor all day.

http://www.off-road.com/tools/gearcalc.html

black_smoke6.9 · 03-22-2005, 06:38 PM

[ QUOTE ]
who ever you spoke with about the lack of 3.73's is a moron, and i wouldnt give him any money.
Try here

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Thanks but the site says that the gear will work in a 1980-1998 my d60 is a 1979. I called them but they are closed I will try again tommorrow. Before I get a bunch of posts that it won't work in my truck. It will work if you move the spring perches and get different tie rods.

Strokerin · 03-22-2005, 06:46 PM

Yeah, I was thinking that I was told not too long ago that 4.10 gears with 35" tires would hang you right in the area of 3.73. Don't remember who told me that, but I hope it helps you out!

86turbodsl · 03-22-2005, 06:53 PM

A D60 reverse cut is a D60 reverse cut. Get the 3.73's. They'll work.

black_smoke6.9 · 03-22-2005, 07:19 PM

Thats what I thought to but when it said 1980-1998 that got me thinkin why wouldn't they work no other web site said anything about that. I believe I am going to stick with the 3.55's. And if I don't like the 3.55's with 35's which I won't get for a while since I already have good tread on my 33's. I can always save up and change them out later. And as recommended earlier If I really need to tow something a long distance through the hills I can put the factory wheels and tires on and hit the road. Thanks for all the help you guys are great.