Is my transmission really dead?

[jw_928]

Hi All,

I just purchased a '91 K5 from a 'friend', and the second day I drove it, I ran into an issue.

I had left in 4Low before leaving work. When I got to the first intersection, I tried to put it into 2wd, but I didn't follow the correct procedure and I think I broke something. Immediately after leaving the intersection, it felt like the transmission was slipping badly.

I checked the fluid and it was very low, so I topped it off to no effect.

The car will move, barely, in forward and reverse. I'm hoping that I just broke some shift linkage or something, but I know nothing about 4WD, so I came here for help.

Is there something obvious I can check?

Thanks,
John

 

[6.2Blazer]

Leaving it in 4 low, or not following some sort of procedure when shifting out of 4 low, should have zero affect on the transmission failing. I also can't think of any type of linkage that would failure and give the same symptons of a badly slipping transmssion.

Now if you are comparing to how the truck felt while taking off in 4 low versus in 2wd high range then there is a substantial difference.

 

[dremu]

I am inclined to say that running the tranny with low fluid is the cause of it slipping, and your (mis)adventure with the transfer case shifting is unrelated.

Sadly, 700R4's (the tranny you have) are known to be weak, and *all* auto trannies do require fluid ... heat is what kills autos first and foremost, and low fluid makes them run hotter.

You might check the fluid level again, as if it was REALLY low due to a major leak or a bungled service, the torque converter mighta been low or empty, so you may have refilled it but not the rest of the tranny.

However, Karnac The Magnificent sees you going to see a good local, non-chain (i.e. NOT Aamco) transmission house fairly soon.

-- A

 

[longbedder]

Sadly, 700R4's (the tranny you have) are known to be weak

I'd say they're more misunderstood than weak...

Go to www.bowtieoverdrives.com and find the page on TV cable setup. Check to make sure yours is functioning properly.

 

[dremu]

I'd say they're more misunderstood than weak...

Go to www.bowtieoverdrives.com and find the page on TV cable setup. Check to make sure yours is functioning properly.

Mmm, fair enough. Certainly they have a bad rap -- early ones with good reason, I gather, later ones prolly due to ignorance.

It's like the 6.2L diesel having a bad reputation from those Oldsmobile 350 diesels ... which, I gather, had their moments, but overall...

-- A

 

[xtrmjoe]

What color is the fluid? Bright red or brick or brown or black?
If the fluid is anything but bright red like it came out of the jug with you need to change it.
To properly fill you may need to cycle thru the gears Forward and reverse a few times. As the torque convertor and all the pasages need to be filled with fluid. Also always check the fluid level with the engine runing in park, preferably at operating temp.
If you pull the pan and find lots of medal in the bottom then you are off for a rebuild.