Nissan 84 pickup transmission problems?

Maintenance/Repairs
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1

okay I no NOTHING about cars/trucks

but I just bought a Nissan pickup (datsun) 84.

and its been driving great

but two nights ago it started idling really high

then one night ago in a drive thru it backfired like a gunshot

now tonite on the way home from work I lost 4th gear, then a few blocks later I lost 3rd…

now Im down to 1st (barely) and reverse.

has my transmission just dropped?

and why /

2

When you say you ‘lost 4th – 3rd – 2nd’, what exactly happens. Is the motor reving up but the truck is not accelerating? Is there any grinding sounds coming from the middle of the truck? Does the shifter feel like you are going into each gear?

I am aiming to determine if you have a transmission problem or a severly slipping clutch. Get back to us with specifics and we can help you further.

3

yes, exactly: the motor is reving up but the truck is not accelerating.
It never ‘locks’ into gear.
like (for lack of a better term) it has zero ‘balls’.
It is weird, like revs real high in RPMs but doesnt quite ever ‘grab’ with almost no acceleration.

4

Assuming that this is an automatic: first, check the transmission fluid - like now - before you drive it anymore. If it is low, find the correct fluid & add to the proper level. Then find the leak and fix it.

If the fluid isn’t low, then you almost certainly need a rebuild. This is a badly slipping transmission.

If it happens to be a manual (unlikely based on your description) then you need a new clutch.

5

I don’t think that the high idle speed and backfiring are related to the transmission. Your problem may be in the clutch. This truck probably has a hydraulically operated clutch–there is a master cylinder that pumps fluid to a slave cylinder that activates the clutch. Have this checked out first to make certain that there is fluid in the master cylinder reservoir and then check for leaks. A mechanic can tell you pretty quickly where the problem might be.

6

Yep, looks like the clutch is toast. On an 84 it might be adjustable. If theres no free play at the top of travel, & if it is adjustable it could’nt hurt to try.

You might get lucky.