*Real* basic questions on rear end
Post Fiend
Joined: Mar 2002
Posts: 19,402
Likes: 38
From: Bonita Springs FL
*Real* basic questions on rear end
I've spent quite a bit of time reading a lot of posts on FTE, and learned a lot about my truck. I've come to the conclusion that I'd like to do two things to it: one, a 4x4 conversion, and two, gear it down to give it more power.
It's currently a '90 F-150 4.9L 2wd with a Mazda 5-speed. I love the motor, but the truck really should have more power. Right now, I have 3.08's in the rear.
A couple questions are: what is meant by measurements of rear ends in inches? I see posts talking about 9" rear ends, 8.8" rear ends, etc. What does that mean? What exactly is 9" in a 9" rear end?
When I start looking to do the 4.10 gears, (I'd also like a limited slip axle) what do I look for? Do I need to replace the entire rear end, or can I just buy the ring and pinion? What else do I need to look for to get the limited slip? If I were to find an entire rear axle from a ranger, for example, what parts could I transplant? Obviously I can't replace the whole rear end.
Thanks for any help..
It's currently a '90 F-150 4.9L 2wd with a Mazda 5-speed. I love the motor, but the truck really should have more power. Right now, I have 3.08's in the rear.
A couple questions are: what is meant by measurements of rear ends in inches? I see posts talking about 9" rear ends, 8.8" rear ends, etc. What does that mean? What exactly is 9" in a 9" rear end?
When I start looking to do the 4.10 gears, (I'd also like a limited slip axle) what do I look for? Do I need to replace the entire rear end, or can I just buy the ring and pinion? What else do I need to look for to get the limited slip? If I were to find an entire rear axle from a ranger, for example, what parts could I transplant? Obviously I can't replace the whole rear end.
Thanks for any help..
Senior User
Joined: Jan 2002
Posts: 262
Likes: 0
*Real* basic questions on rear end
The measurement in inches is the size of the ring gear. When changing the gears and adding a limited slip you don't need a whole new rear end. You just need the ring and pinion, the LS unit itself, and probably some shims and new carrier and pinion bearings.
-Cope
95 F-150 4x4
4.9L M5OD
Front Truetrac Rear Detroit
3.73 Precision Gears
Warn Premiums
4" Superlift Superunner
-Cope
95 F-150 4x4
4.9L M5OD
Front Truetrac Rear Detroit
3.73 Precision Gears
Warn Premiums
4" Superlift Superunner
Elder User
Joined: May 2001
Posts: 662
Likes: 0
From: washington
*Real* basic questions on rear end
Rangers use 8.8's I believe while your f-series uses 9" (I'm not an expert in 150's or rangers so don't quote me on that). Like the previous poster said, to lower your gears you will need to buy a ring, pinion, and carrier. You can actually find what they call "Third Members" which contain the entire unit. A Third Member can be bought with limited slip and any gear ratio you want installed. So all you have to do is pull the axles out and take the old Third Member out then install the new one.
Installing a ring, pinion, and carrier into a Third Member does take alittle knowledge. It is not hard but you need the right tools. You have to set the bearing preload and then the backlash. If you need me to go into detail about that then post and I will.
I've seen complete Third Members with limited slip for about 700.00. This sounds high until you price the limited slip itself and find that they run about 400.00 alone....
Good Luck!
Installing a ring, pinion, and carrier into a Third Member does take alittle knowledge. It is not hard but you need the right tools. You have to set the bearing preload and then the backlash. If you need me to go into detail about that then post and I will.
I've seen complete Third Members with limited slip for about 700.00. This sounds high until you price the limited slip itself and find that they run about 400.00 alone....
Good Luck!
