jay anthony

Hi I have a 90 f150 with a manual 5 speed trans

I’m trying to diagnose a shifting problem.
When stopped it shifts into any gear just fine,
But when driving and shifting up it shifts a bit rough.

Now downshifting is the big problem, most of the time
It doesn’t want to go into gear unless I force it, no grinding
Thought its like if I was going 50 and tried to shift into first
That’s the best way I can describe it.

Any input would be great. Thanks.

J.A.C

how long ago did u replace the clutch. check fluid level

flareside_thunder

JAC gave you a good start...I'm subscribing.

Just call me Sean

iTrader: (1)

I'm going with the clutch isn't releasing all the way or shifter bushings.

jay anthony

The truck has been doing it from when I bought it.
Fluid level is good.
Someone told me it could be bad syncros, not sure if it applies to my problem though.
Also I forgot to mention double clutching makes it shift pretty well smooth.

Just call me Sean

iTrader: (1)

Sounds like mine. Getting the clutch right helped a lot and I think the bushings will take care of the rest.

jay anthony

Could it be I’m using synthetic ATF?
I’ve been reading it can cause problems.

J.A.C

are u using ATF for ur manual transmission . check ur manual it should say what type to use . i use 90 W on my 84 BroncoII transmission.

jay anthony

ATF in a manual trans is strange to me.

This is everything my Haynes manual calls for
“ 4speed 1992 and earlier 80W
4 speed (1993 and on) and 5 speed mercon”

I have the five speed.
I just thought synthetic would help as its an older truck.
Now im reading things saying synthetic could mess up the syncros.

J.A.C

jay anthony i have a haynes book 1980 -1990 and it say u have to use 80W for manual transmission. i know ATF its too light for manual tans.the gears inside do lot of work and have to stay cool as much as they can . i know some people use synthetic for auto trans. but not sure if u can use it on manual.