I am installing a 91 Camero dash cluster in my vette - I needed a "yellow box" vss buffer. I went to a boneyard and pulled what I thought was one from a stripped 1500 pickup. It has a delco PN 16185453 - also delco "QDU 16185645" The box is white but identical to the pics of the yellow units I've seen on this forum. I pulled a large piece of the cable harness and there are 9 wires going into the larger connector on the box. There are no wires going to the 4 pin connector that is used for power on the yellow box. Google can't find anything with these delco numbers - anybody know what this is? Is it just another version of the yellow buffer?. All I need is the frequency divider 4000ppm to 2000ppm. Any help would be appreciated.

Well, I found the answer to my question. For those that may fall into this trap - the 90 - 95 chevy trucks do not use a 4000ppm vss. They use a pinion mechanism that generates 82000ppm and a buffer that processes that. It looks like,smells like but is not a 4 0ut vss buffer. I am now the proud owner of one of these and I still need the 4 out.

Hopes this keeps someone elss from making this mistake - I just did not do my homework.

I'm pretty sure that the one from my S10 Blazer is the same as you describe..... plastic box in the same form but wrong color ! The truck is a 91 S10 Blazer Blazer 'Sport' with a factory digital speedometer.

I no longer feel the need to plug my white box into a thirdgen just to see what would happen ! Thanx for saving me from wasting that time & effort !

You are right John - the S10 is included in the units that run this DRAC or QDU module.

Bill