Was towing my car trailer down Bear Creek Road towards 880 today and the 93 Suburban shut down on me twice after down shifting into 1st gear!!! Not exactly confidence inspiring when you are trying to slow down on a steep grade for a hair pin turn. The first time it happened I did not know the engine cut out as the truck still decelerated its just when I went to accelerate there was no responce at first I thought the fuel pump cut out but then I realized the engine was still turning 3000 RPM but was just turning because the tires were still turning thru the transmission so I just coasted to a turn off put the truck in neutral and restarted the motor. The second time a few turns up the truck did the same thing so I just neutraled the tranny and restarted on the run but shifting to neutral is not something u like to do towing down Bear Creek lol! No check engine light when it happened and none since. Need less to say I did not downshift to 1st after those two incidents. Any idea what might be going on??? I drive the truck on this road regularly and often downshift it into 1st and have never had a problem. I might add that the past couple days I've had the antilock light come on upon starting up the truck about every other time and when the light is on I can lock up the brakes which tells me the anti lock brake system is not working properly. It usually goes off the next time I start the truck. I have been noticing I get the antilock pumping/buzzing sound when I down shift the truck sometimes into 1st gear so I'm not sure if this is related to the stalling problem or not--braking is strong none the less???? Will a code reader tell me anything since this truck is OBD 1 I believe? Will a OBD 2 code reader plug into this truck since my only OBD 1 reader is for a Ford trucks?

Thanks in advance,
Jason :)

Stop by autozone.
They will normally read the codes for you for free.

Thanks I'll try and stop by there!

Check the VSS circuit for proper function.

I'll check it out...whats odd is I've not had this happen again since then or before then--only when i was towing??? It was like a "flame out" condition. The first time it happened I got a few backfires as the engine approched idle speed and I tried pumping the gas--just weird???

Thanks for the tips so far...

Jason :)

So now the transmission occasionally has a tendency to drop into 2nd gear just driving down the freeway at a cruise. So I need to pull some codes but I'm guessing a throttle sensor or something similar is acting up. Well I'm hoping so cause I don't really fell like pulling the transmission and fitting up a rebuilt unit just now...

Jason :)

Guess it wasn't that big of a concern since it's been over a month and you have pulled the codes yet.

A buddy of mine had a RV that the speed sensor went out it did the bullshit of down shifting in 2nd and then just stayed in there. Don't know if its related but just info.

Isn't your speedo electronic? Driven by the VSS?
Also, to access codes on OBD-I GM's, just short pin A to pin B on the ALDL, turn on the ignition key, and count the flashes indicated on the "check engine " light.
Pulling codes is easy on the OBD-I GM ECM/PCM.

Thanks for the tips. I have never pulled the codes on this truck so I'll have to do some research lol. I have some code readers just never used them on this model of truck. Anyway I found I can shift it out of 2nd gear by shifting the transmission manually otherwise yes it will stay in second. It would be great if this is all thats wrong with it lol. I basically limped it to my shop and its been parked there and I've been using my other vehicles (they all get better MPG anyway) but now that gas is much cheaper I can probably afford to take the Suburban out on trips again lol!

Jason :)