I just changed my gears from 3.55 to 4.56 in a 1990 F250. How do I adjust my speedometer. Also what is the best way to drain the rear end after a good break in period?

 

You will have to get another speedo gear.

 

Just pop off the cover. Wipe the innerds out. Buy a $1 pocket combination screwdriver/magnet. Pull out the magnet. Drill a 3/8" deep hole in the drain plug (for a slip fit for the magnet). "Stake" the magnet to the drain plug (center-punch 3 dimples around the magnet) -- to guarantee that it won't fall out. Put the cover back on (new gasket). Fill with appropriate synthetic hypoid gear oil. Clean driveway.

 

You are saying that the stock Ford Diff drain plugs/bolts do not have built in magnets like my Toyota!
It's just like all the missing zerk fittings to lube the front-end and drive shafts!


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'99 White, F150 XLT, SuperCab, StyleSide, 4WD, 5.4L, 3.55 Open diff(yuk!), K&N Filter, Gibson Cat-back, Jet Perf. Chip,
Rancho RS5000, AMP Bed X-Tender, Muth Signal Mirrors, Cobra CB
Future mods:
WMS Vel tube-ordered 3/2/00, thinking about Poweraid throttle body spacer(air vortex'r)

 

Or, could it just be that Ford cleans out their axles Before shipment, and doesn't need to catch the metal chips with a magnet like some trucks-of-a-lesser-god?

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Y2K XLT EC 5.4L 7700# SB 4x4 w/LS 3.73 (repeat buyer)

 

I thought those metal chunks sticking to the magnet were from the gears! Do you mean to tell me that they are just left over from the manufacturing process?!?!