Auto Tranny Slip/ ABS light

[Jimmy.Spekta]

First, Salutations!

 

Just bought my Pathy last night. '94 XE 3.0E 280,000+ miles on her. Certainly in need of some TLC, but a beautiful truck nonetheless.

 

Driving at both highway and city speeds tonight, there were 4 separate instances where I felt the tranny slip momentarily. The tach would jump, then settle. After it would do this, the ABS light would flicker for a moment, then go out, and it drove as well as it's going to in it's current state.

 

Curious if anyone has any possible idea what this might be. Because even though my girl is very "seasoned", if the tranny is on the way out after I bought it only 24 HOURS AGO...

 

o.O *twitch*

[Towncivilian]

The stock transmission cooler on WD21s is prone to clogging if the fluid has not been properly maintained. If there isn't an auxiliary transmission cooler already present, you should purchase the largest one you can afford and fit, and bypass the stock cooler. An in-line filter is also a good idea.

 

What's the condition and level of the transmission fluid?

 

1. Drive around for 10 minutes in the city after the transmission is at operating temperature.

2. Park on level surface and apply parking brake.

3. With P selected, shift through every gear and return to P.

4. Pull transmission dipstick with engine idling, wipe clean, reinsert completely, and read level. It must be within the notched areas labeled "HOT". Check for fluid contamination after wiping on a paper towel.

 

The fluid should be red, and not smell burnt. If it is brown/black, smells burnt, or metal flakes are visible, do several drain & fills, each within a few days of each other, or do a pan drop to change the in-pan screen and clean the pan of contaminants then a few drain & fills, or a cooler line exchange.

 

As for the ABS light, I'm not sure. Is the brake fluid at the MAX line in the reservoir? I think dirty fluid can impact ABS operation, so maybe bleed your brakes if the fluid looks excessively dark.

 

Congrats on the purchase, and welcome to NPORA! Download a copy of the factory service manual here for future use, it'll prove invaluable.

Edited November 9, 2011 by Towncivilian

[silverton]

These trucks only have rear ABS and no special fluid. Just the brake fluid with an actuator on the right side frame rail. I would do as towncivilian suggested with checking the fluid. and at 280k miles, I'm surprised the auto in your truck has last so long! They usually fail around 170-200,000. So who knows, the transmission may not even be original.

 

But, your abs speed sensor could be going out, it's in the top of the diff and is the most common culprit for the light.

[adamzan]

Are you sure it just isn't' the torque converter unlocking and locking? I find it unlocks fairly easily on these trucks, even on the highway.

 

Also since the abs light comes on at the same time I would start looking into a possible electrical problem, there is a detailed diagnostic for the transmission in the FSM (factory service manual).

[1994SEV6]

At 280k miles...I wouldn't be blaming anything. If the transmission goes, that's 280k miles for ya. Ford transmissions are junk after 100k! Nissans are tough for sure, but give it a break.

 

As far as your actual problem, it sounds like you are describing "shift flare". This is when the transmission slips right BEFORE shifting and the RPMs jump up.

This is a good quote I found. This pretty much describes it "Shift flare is when the RPM briefly increases on an upshift. RPMs should always decrease on an upshift."

 

As far as the ABS light, I'm not sure what that is. With my experience, if the brake fluid is low, BOTH the "brake" light and the "abs" light come on. If it is just the ABS light, it might be a sensor problem. It coming on when the shifting problem occurs is weird, but I wouldn't worry about it. These trucks only had ABS on the rear, and the rear only does about 10% of the braking. Not really that important.