For a while, well a long time now I have been reading and reading in regards to the upgrade of gearīs, my truck is 2000 4x4 5.4 lt, it came with 3.55 l.s..

What I need from you guyīs is your opinion and better yet your advise, since the first thread concerning upgrade of gearīs I was confused due that I never looked in the signatures of the person who opened the thread or the one replying, 90 percent of those who change their gearīs from 3.55 to 4.10 had the regular gearīs from factory and were upgrading to 4.10 l.s. or from 3.55 to 3.73l.s. etc.etc. this by part had me confused when they said I got (example) prsicion gears with auburn limited slip, or otherīs wanted powertax, this was the part that had me thinking why purchase ring and pinion and auburn limited slip or other brandīs if the truck came with limited slip.

What I am looking is for upgrading from 3.55l.s to 4.10l.s for both diff. would I need the same gears for the front as for the rear, in my case that I have a 4x4 who carry the best gears and what would be the price range. I have 31 in. tires and my truck feels sluggish, eventhough I have a Borla cat back sistem, k&n, superchip and many other goodies but even so it feels slow.

 

Welcome !! Since you have a LS differential in the rear already, you can re-use it. There are other aftermarket differentials on the market. So, for the rear, you will need a gear set and an installation kit for a 9.75" axle. On the front, you will need reverse cut 8.8" gears and an installation kit. You will need the same ratio for the front and the rear. You have fewer gear manufacturers and ratios with the 9.75". The 9.75" rear-end has several versions, so, you need to find an gear and kit that is for the 2000 or newer truck. For an example, Precision Gears ring and pinion and installation kits have an "L" added to the part numbers for 2000+ applications. To have both axles done professionally would cost approximately $1,200. After researching this topic thoroughly, I haven't found anyone more knowledgeable than these folks:
www.reiderracing.com

 

Firts of all I dont want to sound ignorant, I thought both diff.īs were the same, 9.75, it is new to me that front are 8.8, like you metioned in using same ratio, it is my intention in using same ratio front and rear (4.10).

Reading another thread you also metioned reiderracing, I contacted them for advise and quotes havent received reply as of yet.

As for prices I was asking for best gear prices, cant find a local dealer that carries them so I must rely on the web, sent almost all the online stores for quotes but no reply also, a friend of mine will do the job as part of a swap .

Max thankīs for your advise, experience talk or are you a mechanic

 

You're more than welcome !! The trucks with the 5.4 engine use a larger rear differential; it's referred to by it's ring size 9.75". The trucks with smaller engines use an 8.8" unit; which is also what your truck has in the front. There are tags under one of the cover bolts to verify this. Call the Reider Racing tech line during normal business hours and ask for Tim King. The rear 9.75" gears cost $275, the installation kit costs $30 for the one without bearings and upwards of $165 for the one with bearings. The front gear set costs less.

 

Those 30 years have been of great help to me, thanks, I will call Tim King first thing monday morning, I will get to you later with update after installed.

 

You're Welcome !! Good luck with your install. Let us know how things turn out.

 

One more question until I receive the gears, I placed the order with Tim King and like you mentioned very nice and profesional, I asked him about if he carried the axle oil, he said that ford recomended their sinthetic oil, but he mentioned to avoid the sinthethic and use a petroleum semi sinthetic or something like that, I was so anxcious after all the information he gave me I realy didnt pay that much of attention to the oil info..

Any Idea of what he was trying to recommend

 

If your vehicle is under warranty, I would use what Ford recommends or better. What Tim mentioned will basically just need to be changed more often. I use this oil, it exceeds everyone's standards. www.amsoil.com/products/tgo.htm

 

just a note...my 98 f150 4x4 5.4 orp with tow pkg came with a 10.25" rear. not the 9.75". I dont know if it was a special order or not. I had assumed it had the 9.75" until I crawled under it and looked. just fyi...

 

weezul22,
I think I have the same situation, but my tag says it is a 9.75 rear. I looked at the Precision Gear website and it looks exactly like the 10 1/4 rear end pictured. I have a 2000 Expedition 4X4, 5.4L w/ tow package,3.55 LS, and 8.8R front axle and want to swap to 4.10.

What did your tag say?

 

Go by what your tag says.

 

i agree...go with the tag unless your willing to open the housing and tear it all apart. my tag says 10.25..like i said before I am not sure if it was a special order or not...does anyone know if any years came with 10.25 when you got the ORP or Tow pkg?

 

Thanks All. I will call Tim at Reider Racing to get things rolling. Will I have to change the carrier in the front?

 

Just mention what you are looking for and he will do the recommendations, I had requested quotes from deffrent dealers and reiderraing prices were the best, just waiting for my buddy to be free so he can install the gears, one more thing shipping was super fast.