Notices
General Automotive Discussion

Axle swap help

Thread Tools
 
Search this Thread
 
Old Jan 4, 2017 | 07:29 PM
  #1  
Diesel_now's Avatar
Diesel_now
Thread Starter
|
Freshman User
Joined: Jan 2017
Posts: 34
Likes: 0
Axle swap help

So I just swapped my rear end on my 87 f250 6.9 because the outer seals and bearings were shot, probably the inner as well, not sure. My new problem (do to lack of research) is that I went from 3.55 to 4.10 gear ratio. The axles are the same thing with different ratios. Would I be able to use the gears out of my old axle? If so, would they have to be re set? Could it be as easy as just swapping the pinion gear? Thanks in advance for any advice.
 
Reply
Old Jan 4, 2017 | 07:51 PM
  #2  
85e150's Avatar
85e150
Super Moderator
20 Year Member
Community Builder
Liked
Community Favorite
Joined: Apr 2004
Posts: 34,475
Likes: 2,800
Club FTE Gold Member
Welcome to FTE.

So you swapped the whole thing, drum to drum? Seals and axle bearings are, imo, a much smaller job.

You can swap your old gears over, but that is way more work than seals and axle bearings.

You will probably never get them back in the same pattern and will soon have a howler out back.

You can not change just one gear, pinion or ring. They are a set. Change one and you will have a howler right out of the gate.

Take your old axle and have the seals and bearings replaced. Reinstall it. Drive on. Serving suggestion.
 
Reply
Old Jan 4, 2017 | 07:55 PM
  #3  
Diesel_now's Avatar
Diesel_now
Thread Starter
|
Freshman User
Joined: Jan 2017
Posts: 34
Likes: 0
Dang

Looks like I have a new lawn ornament, good thing it's at my brother in law's house. How much would a shop charge to swap em?
 
Reply
Old Jan 4, 2017 | 10:19 PM
  #4  
85e150's Avatar
85e150
Super Moderator
20 Year Member
Community Builder
Liked
Community Favorite
Joined: Apr 2004
Posts: 34,475
Likes: 2,800
Club FTE Gold Member
Since the old axle is out, take it to a shop you trust and get a quote. Swapping the old gears to your "new" axle is a non-starter. Just get your old one fixed and reinstall it. Serving suggestion.
 
Reply
Old Jan 5, 2017 | 02:14 PM
  #5  
Diesel_now's Avatar
Diesel_now
Thread Starter
|
Freshman User
Joined: Jan 2017
Posts: 34
Likes: 0
Dang

Thanks for the advice. Should have done that in the first place. What if I took the five speed transmission from the truck that I got the new axle from? I don't know which would be easier but swapping transmission will be a lot cheaper. I just wonder if I would have a more reasonable final drive ratio.
 
Reply
Old Jan 5, 2017 | 03:35 PM
  #6  
tjc transport's Avatar
tjc transport
i ain't rite
Joined: Mar 2005
Posts: 65,455
Likes: 5,526
From: Marlboro Mental Hospital.
Club FTE Gold Member
going from 3.55 to 4.10 gears will give you a little more power, but less top speed. and a little less fuel mileage. as long as hte truck is a 2 wheel drive it is no that big of a deal.
but swapping the 4 speed manual trans for a ZF 5 speed is a popular upgrade because it gives you overdrive.
and it is not that big of a deal, as long as the trans is off a diesel engine. gas trans will not bolt to a diesel.
 
Reply
Old Jan 5, 2017 | 04:28 PM
  #7  
Diesel_now's Avatar
Diesel_now
Thread Starter
|
Freshman User
Joined: Jan 2017
Posts: 34
Likes: 0
You said the zf has overdrive which would help immensely. Would it have higher or lower gears than my current four speed? Or about the same? If I had another gear I would be more than happy the axle gearing I now have. If the five speed is lower geared than my current transmission then it wouldn't help too much. Also I will have to use my current transfer case. Thanks for all the help
 
Reply
Old Jan 5, 2017 | 05:54 PM
  #8  
tjc transport's Avatar
tjc transport
i ain't rite
Joined: Mar 2005
Posts: 65,455
Likes: 5,526
From: Marlboro Mental Hospital.
Club FTE Gold Member
ooofff. four wheel drive..
you are going to have to either change the front axle to 4.10 gears, or swap the rear back to 3.55.
yes, the ZF is a 5 speed with overdrive. it is basically the same as your current 4 speed plus an overdrive gear. first is not as bad as the granny creeper gear you currently have.
if it is a 4X4 trans, your transfer case will bolt on.
i personally would leave the 4.10 gears in it with the 5 speed, it will make it better powered with the 6.9 than with 3.55's
 
Reply
FTE Stories

Ford Trucks for Ford Truck Enthusiasts

story-0

Top 10 Ford Truck Tragedies

 Joe Kucinski
story-1

AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make

 Brett Foote
story-2

Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!

 Michael S. Palmer
story-3

Ford's 2001 Explorer Sportsman Concept Looks For a New Home

 Verdad Gallardo
story-4

10 Best Ford Truck Engines We Miss the Most!

 Joe Kucinski
story-5

2026 Shelby F-150 Off-Road: Better Than a Raptor R?

 Brett Foote
story-6

2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!

 Michael S. Palmer
story-7

10 Most Surprising 2026 Ford Truck Features!

 Joe Kucinski
story-8

Top 10 Ford Trucks Coming to Mecum Indy 2026

 Brett Foote
story-9

5 Best / 5 Worst Ford Truck Wheels of All Time

 Joe Kucinski
Old Jan 5, 2017 | 06:00 PM
  #9  
Diesel_now's Avatar
Diesel_now
Thread Starter
|
Freshman User
Joined: Jan 2017
Posts: 34
Likes: 0
Thanks for the input. I think that is exactly what I will do. I have easy access to the transmission and front axle, and can get them for cheaper than my local wrecking yard would sell them for. Kinda seems like a blessing in disguise now. Thanks again everyone.
 
Reply
Old Jan 6, 2017 | 04:41 AM
  #10  
tjc transport's Avatar
tjc transport
i ain't rite
Joined: Mar 2005
Posts: 65,455
Likes: 5,526
From: Marlboro Mental Hospital.
Club FTE Gold Member
what is the parts truck? if it is a F350 you will get the better front axle too.
if a 350, grab the front springs, steering parts, trac bar, and bracket while you are under there, the 250 springs are way too stiff for a solid axle and will give a rough ride.
 
Reply
Old Jan 6, 2017 | 06:37 AM
  #11  
Diesel_now's Avatar
Diesel_now
Thread Starter
|
Freshman User
Joined: Jan 2017
Posts: 34
Likes: 0
Parts truck is an 88 f250. I guess that's when they switched over to the 7.3. Had to get a u joint to go from 87 to 87 as they are different sizes and I didn't have the drive shaft from the 88. I don't have the transfer case either so I hope mine doesn't reduce the gears any further. A solid axle would be nice but I like the old Ford ifs over anything else I've worked on and is a comfy ride. I wish I could use coil springs but I'm not aware of any that will hold the weight of the engine.
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
redbayredneck
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
8
Feb 15, 2016 05:53 AM
BBslider001
1994.5 - 1997 7.3L Power Stroke Diesel
14
Jun 29, 2014 08:29 PM
IDIDieselJohn
Pre-Power Stroke Diesel (7.3L IDI & 6.9L)
3
Jun 18, 2014 10:51 PM
48' fordster
Clutch, Transmission, Differential, Axle & Transfer Case
1
Jan 12, 2012 08:55 PM
khardrunner14
1987 - 1996 F150 & Larger F-Series Trucks
11
Jan 27, 2010 07:24 PM




All times are GMT -5. The time now is 06:31 AM.

story-0
Top 10 Ford Truck Tragedies

Slideshow: Top 10 Ford truck tragedies.

By Joe Kucinski | 2026-05-18 19:34:33


VIEW MORE
story-1
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make

And it might be even better than that.

By Brett Foote | 2026-05-18 19:26:42


VIEW MORE
story-2
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!

Slideshow: Does lowering an F-150 Lobo RUIN the ride quality?

By Michael S. Palmer | 2026-05-18 19:20:37


VIEW MORE
story-3
Ford's 2001 Explorer Sportsman Concept Looks For a New Home

Slideshow: Ford's bizarre fishing-themed Explorer concept has resurfaced after spending decades largely forgotten.

By Verdad Gallardo | 2026-05-12 18:07:46


VIEW MORE
story-4
10 Best Ford Truck Engines We Miss the Most!

Slideshow: The 10 best Ford truck engines we miss the most.

By Joe Kucinski | 2026-05-12 13:09:47


VIEW MORE
story-5
2026 Shelby F-150 Off-Road: Better Than a Raptor R?

Slideshow: first look at the 810 hp 2026 Shelby F-150 Off-Road!

By Brett Foote | 2026-05-12 12:50:07


VIEW MORE
story-6
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!

Slideshow: Everything You Need to Know about the 2027 Super Duty Carhartt Package!

By Michael S. Palmer | 2026-05-07 17:51:06


VIEW MORE
story-7
10 Most Surprising 2026 Ford Truck Features!

Slideshow: 10 most surprising Ford truck options/features in 2026.

By Joe Kucinski | 2026-05-05 11:17:22


VIEW MORE
story-8
Top 10 Ford Trucks Coming to Mecum Indy 2026

Slideshow: Here are the top 10 Fords coming to Mecum Indy 2026.

By Brett Foote | 2026-05-04 13:49:49


VIEW MORE
story-9
5 Best / 5 Worst Ford Truck Wheels of All Time

Slideshow: The 5 best and 5 worst Ford truck wheels of all time

By Joe Kucinski | 2026-04-29 16:49:01


VIEW MORE