Newbie Tech Section Often asked technical questions can be asked here

does re gearing help with MPG's?

Thread Tools
 
Search this Thread
 
Old 03-19-2011, 01:35 PM
  #1  
Registered User
Thread Starter
 
skoti89's Avatar
 
Join Date: Jul 2010
Location: Carson City
Posts: 538
Likes: 0
Received 6 Likes on 5 Posts
does re gearing help with MPG's?

I know, very newb question. I'm just killing my wallet with stock 4.10's and 33x12.5x15. I know the wider tires have a lot to do with it. I was running 31x10.5x15 and getting about 16 around town, with same gears Im getting about 12 to 13. My plan is 35's no bigger, and 5.29 gear ratio. I'm not going to re gear until I do a SAS this summer.

Fresh rebuild with about 1000 miles, new plugs, wires, cap, rotor, fuel filter, and 5w 30 synthetic etc...

This is my daily driver, but I wheel every other day. I know there is a point where a 4x4 and good gas mileage don't really go well together, but its a 22re. This dumb ass sold his honda civic for this last year....lol

I would be happy with 15 to 16 around town again.
Old 03-19-2011, 01:55 PM
  #2  
Registered User
 
vang_22re's Avatar
 
Join Date: Jun 2009
Location: Fresno, Ca
Posts: 719
Likes: 0
Received 0 Likes on 0 Posts
It will help A LOT!! You will not regret it one bit.
Old 03-19-2011, 02:08 PM
  #3  
Registered User
 
toyota4x4907's Avatar
 
Join Date: Sep 2008
Location: middle of no where Alaska
Posts: 4,355
Likes: 0
Received 2 Likes on 2 Posts
Your MPG average is down because you wheel every other day. You may actually drive 18 miles per gallon on the street, but your average will be lower because of the wheeling- low speed, 4x4, skinny pedal here and there, pulling your friends out, idling for extended periods of time.
Old 03-19-2011, 02:21 PM
  #4  
Contributing Member
iTrader: (3)
 
4Crawler's Avatar
 
Join Date: Jun 2002
Location: SF Bay Area, CA
Posts: 10,817
Likes: 0
Received 29 Likes on 26 Posts
My '85 did best with 33s w/ 5.29 gears. Later I switched to 4.88s and the MPG dropped about 10% (both corrected).

And with the 4.10s and 33s, are you correcting the actual miles driven for the larger tires? If not, you are actually driving about 18% farther than the odometer registers with the taller tires.
Old 03-19-2011, 02:29 PM
  #5  
Registered User
Thread Starter
 
skoti89's Avatar
 
Join Date: Jul 2010
Location: Carson City
Posts: 538
Likes: 0
Received 6 Likes on 5 Posts
Originally Posted by toyota4x4907
Your MPG average is down because you wheel every other day. You may actually drive 18 miles per gallon on the street, but your average will be lower because of the wheeling- low speed, 4x4, skinny pedal here and there, pulling your friends out, idling for extended periods of time.
I have taken that into account. there has been times when I haven't for a week or two, that where I get my around town mileage. I dont calculate it if I have been in 4wd or 4 lo

theres just a spot on my way home from work that I like to hit after work a couple times a work week
Old 03-19-2011, 02:38 PM
  #6  
Registered User
Thread Starter
 
skoti89's Avatar
 
Join Date: Jul 2010
Location: Carson City
Posts: 538
Likes: 0
Received 6 Likes on 5 Posts
Originally Posted by 4Crawler
My '85 did best with 33s w/ 5.29 gears. Later I switched to 4.88s and the MPG dropped about 10% (both corrected).

And with the 4.10s and 33s, are you correcting the actual miles driven for the larger tires? If not, you are actually driving about 18% farther than the odometer registers with the taller tires.
Ha! geez. didn't even think about that.

I ran out of gas, put it 10 bucks( 2.5 gallons) then ran out again after going 30 miles. about 12 mpgs( I know, bad on the fuel pump, but it was the day before pay day and I ran out of change...). Thats also about the same reading I get when I fill up all the way, keep track of miles, then fill up again and divide the miles by how many gallons I put in again.

So I'm actually getting maybe 15? Im horrible with math. whatever the 12 mpg's plus 18 percent is...
Old 03-19-2011, 02:46 PM
  #7  
Contributing Member
iTrader: (3)
 
4Crawler's Avatar
 
Join Date: Jun 2002
Location: SF Bay Area, CA
Posts: 10,817
Likes: 0
Received 29 Likes on 26 Posts
12 uncorrected is about 14 corrected. Just multiply MPG by 1.18 to get the actual figure.

Plus, if you are on the highway, realize that you are also driving 18% faster than the speedo says, so higher speed = more load on engine = less MPG. So at 65 indicated, you are actually going around 76-77. I know on my '85, at 65 I'll get around 18 (33s and 4.88s) and if I keep the speed to 55, I'll get 20 or a little better. When I ran 5.29s, I used to get like 20-22 @ 65+ and maybe 22-24 @ 55 or so.
Old 03-19-2011, 03:01 PM
  #8  
Registered User
Thread Starter
 
skoti89's Avatar
 
Join Date: Jul 2010
Location: Carson City
Posts: 538
Likes: 0
Received 6 Likes on 5 Posts
always great information roger, thank you
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
mskalmus
86-95 Trucks & 4Runners
9
05-28-2017 07:51 AM
wolfpackfan33
Pre 84 Trucks
2
08-02-2015 03:36 PM
Shaun Crystal Gomban
Pre 84 Trucks
5
07-30-2015 10:13 PM
coffey50
Offroad Tech
17
07-28-2015 10:55 AM
justdifferentials
Just Differentials
0
07-22-2015 08:26 PM



Quick Reply: does re gearing help with MPG's?



All times are GMT -8. The time now is 05:34 PM.