I own a '93 F-150 4x4 with the 351w and the E40D. I have been having trouble with my speedometer jumping around a little. When I get around 70 mph it starts to jump. It only jumps 10 mph, but it gets annoying. Thanx for any input.
-Jason-

 

Yer problem is the speedometer gear located in the ##### end of the transmission. Looking at the rear of the tranny, you'll see a cable that goes into the rear and some type of bolt and cover thing. Take that out and I bet ya that you got a stripped speedo gear. The same thing happened to my 84 f 150 w/ aod and 302. Good luck findin a new speedo gear, you'll probably have to look at a dealer or junkyard. If you look at a junkyard, look for a good gear that has no missing teeth or is stripped in any way. They are usually plastic and wear out. Make sure you use a good grease on the new one to prevent wear.
Good Luck

 

Actually , On 1993 4WD trucks the speedometer gear is located at the end of the transfer case . They are color coded , different colors denote different numbers of teeth on the gear . Its not nessecary to lubricate them with anything , they are lubricated from the transmission fluid in the transfer case .

 

92 and later have electronic speedometers. Check the abs sensor on top of the rear differential for debris. I have read on other boards this is a sign the diff is going out.

 

Any other information would be appreciated. Thanx so much for the information already. I really hope it's not any of these. I don't have the patience or the budget.
-Jason-

 

Sorry , I thought the Electronic speedo controls started with a later model yr than 1994 , Sorry for any confusion .

 

no problem, I appreciate all the help!!
-Jason-

 

Do you have any problem with your truck stalling at take off? A dead spot at 2-3mph where your engine just wants to shut off? If you are not sure, try idling and going 0-10mph very slowly and see if at any time you engine wants to die. If it does, that could possibly be a bad PSOM (programmable speedometer/odometer module) which is the name for your speedometer. If not, then i would drain the fluid and remove the differential cover to check the condition of the internal components. Someone else will have to give you the details, i'm unsure, but the speed sensor on top of the differential uses some kind of sensor on the ring gear to detect the speed. If something is misaligned by a small amount, it can cause the needle to bounce like that. You might want to check out the wiring too. Trace the wires going to the speed sensor on the differential as far as you can. Check for cut wires or corrosion on the sensor terminals. If there is a bad connection it can mess up your needle too.


Primary rig is:
95' F-150 EB 300/6 5 spd with 4" Superlift, MSD, Ram Air, Gibson Exhaust, 32" BFG Muds
NEW PICS IN MY GALLERY!! :-)


Then theres:
88' F-250 Superduty 351 + c6
92' Thunderbird 3.8L V-6 FOR SALE!
95' Mercury Cougar 4.6L V-8
80' E-350 300/6 and a
3 spd column shifter baby.

The newest addition to the Ford family is a 99' Mustang GT 4.6L

 

[updated:LAST EDITED ON 08-Apr-02 AT 09:02 PM (EST)]Edit: I see Mustang beat me to it, must of posted at the same time

I hate to give you bad news, but it's probably your PSOM (programmable speedomoter odometer module- the speedometer in the dash) that's bad. These aren't cheap from the dealer either, finding a used one would be much cheaper. I'm still trying to figure out which years will work because I have your exact same problem. Of course, I'd first check the easy stuff- the sensor and wiring on the rearend. Is your ABS light ever on?

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[font color="green"]1995 F-150 Supercab XLT 4x4 LWB 302 M5OD [/font]31x10.50's
[font color="green"]1986 F-150 4x4 300 I6 NP435 [/font]Warn hubs, DeeZee bed caps, '96 XLT bench seat, new paint job