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Lock Cylinder Replacement

I need to replace the ignition lock cylinder on a 2003 Trailblazer. I don’t have my old key which is why I bought a new cylinder with keys. However, all the How-To’s I come across require the key. So I need to know how to replace the cylinder without having the key. ANY help would be MUCH appreciated. Thanks…

Have you tried going to the dealership to see about getting the proper keys for this truck? If you can satisfactorily prove ownership, they will sell you a key that will fit the doors and the ignition lock. Alternatively, you could remove a door lock cylinder and have a locksmith make a key to fit that so you don’t have to worry about removing the ignition lock.

I have my Title and picture ID, but I don’t have $80 to have a new key made. My cheapest alternative was to get a new ignition cylinder.

Seek the services of an automotive locksmith who has the skill and tools to change the cylinder…Or make the $80 donation to the dealer. Forget DIY…

You need the old key to remove the old lock cylinder. The only way around this is to try drilling and chiseling out the old one, which is very likely to cause damage to your steering column. Alternatively, you could buy a used steering column, which will come with the key for that column, and replace the steering column. You could also hire a locksmith to remove the old lock cylinder. They may have a tool to strike the pins to cause the lock to release, allowing the cylinder to rotate so it can be removed. By far the best, cheapest, and easiest way to deal with this problem is to pay the dealer the $80 for a new key. You even get to keep your single key locking that way, so you can continue locking your doors. It might be cheaper to have a locksmith make a key to fit one of your door locks, but you still have to take one of your doors apart to get the lock cylinder out of it to take it in to have that done. If I were in this situation, I would just pay the dealer and make sure not to lose the keys again.

This is one of many cases when cheaper isn’t necessarily easier and is certainly not better. These days, $80 for a duplicate key is not bad. Many duplicate keys now run a few hundred bucks.

Are you comfortable with the beginning steps,getting the airbag off removing the steering wheel with a puller then getting the lock plate off with a lock plate removal tool? These beginning steps only take about 20 min. and the rest of the job is not so extreme but if you place any value on your time it will not be hard to eat up $80.00.

If you did master these steps and bought the two pullers (probably under $20.00 each from Harbor Freight or a place like Harbor Freight) you would be setup to do you T/S switch if it ever went bad. Pay attention you do not break horn wire retention tab on the T/S cancel cam. This happens when you are either taking the airbag off and it falls in your lap or putting it on when and it again falls in your lap. There are some pretty unique torx screws you will need to remove for the lock cylinder itself(another socket to buy) for this job also.Last one I did was probably a 2000 but the job should be very similar if not exact.

Oldschool makes a good point about having to purchase quite a few tools to do this job that a lot of people don’t already own. The only reason most people would own the tools you need to do this job is if you regularly perform work like this. It’s easy to eat through $80 pretty quick by purchasing tools and breaking other incidentals, like the clock spring tab for the horn wiring. Anybody who has ever removed an airbag or steering wheel from a GM has broken at least one clock spring tab. And even after you disassemble the steering column, you will STILL need the lock cylinder in the “run” position for it to slide out of the column once the retaining bolt is removed. I think I have removed one of these successfully without getting it into the “run” position without damaging the steering column, but it has been years since I did it and don’t remember how I managed to do it, but there was some careful, selective damage done, and I don’t suggest it on a vehicle you care about. If this is a junker you don’t really care about or need, and you want to experiment, I say go for it and try to install that lock cylinder. If you need the car to run and drive, and don’t really want to have to replace the steering column, I say abandon this project, return your lock cylinder, and go to the dealership and get another key made. There’s too much potential risk here to save $40 on this project (Rock Auto lists ignition lock cylinders for this vehicle for $33-42 plus shipping).

Door lock cylinders have less wafers than ignitions do, to save money in production.

The mobile locksmith I know, in most cases, can cut a key from the VIN without dealer help. There are information services available for mobile locksmiths that provide this info.

The Rub

The anti thief system on your ride may not allow any of the suggested fixes to work. So no matter what way you replace your key, you may need a key programmed to allow the rig to start. So, I would find a mobile locksmith with the ability to reprogram keys and find out the ?cut code? for the key. One stop shop and he comes to you.

You will have a ?SECURITY? lamp on your dash that reports problems with tampering.

[i] I don't have $80 to have a new key made.[/i] 

That does not sound like it is too expensive.   I suspect no matter how you end up fixing it, you are likely to be out at least that much or close to it.

I did this once on my Dodge, actually to replace the switch behind the lock. I had the factory repair manual to guide me through the job, and it was not difficult at all. I don’t know why someone mentioned the airbag. This is not a factor at all.

But I do recall I needed the original key to turn the lock to the correct position for removal, and I had to purchase a special set of sockets called security torx. If you don’t have manual, key, and torx, then you need to find someone to do the job for you.

Because we don’t have the key so he must come in through the top to get the lock cylinder out,if you come in through the top you have to take the steering wheel off,to take the steering wheel off you need to take the airbag off. I guess you could just slidehammer the lock cylinder out of it’s housing but I was going for a way that no damage or work marks would be visible. If you know of a way to get the cylinder out when you don’t have the key and don’t want to do visible damage let us know. It is possible to get the plastic housing that covers the area where the lock cylinder is located off without taking the steering wheel off (it is in two pieces) but this is a bit of a challenge and I don’t think it will get you closer to getting the old cylinder out when you do not have a key.

On a Dodge, the airbag is not a factor, nor is it a factor on most Fords, which allow you to remove the lock cylinder without removing the steering wheel. All makes, however, require the old key to remove the cylinder. If the old key wasn’t required, anyone could steal a car and simply swap out the ignition lock cylinder to have an operable vehicle with no evidence of any foul play. The OP’s best bet in the matter will be to return the new lock cylinder, get a couple more twenties, and have a new key made by the dealer. Cheap, simple, no muss, no fuss. Unless it’s a junker, but I doubt an '03 Trailblazer is a junker.

You see why I do not respond to FORD,Dodge,posts, I simply do not know those cars.

I would prepare as if you had the ignition key. Then when it comes time to remove the lock cylinder with the key, substitute a big screwdriver and force the lock cylinder to the position required. I’ve also used a slide hammer to yank lock cylinders.


The last Chrysler I did was a Caravan, which required removing the plastic collar from the steering column in order to access a little “button” to release the lock cylinder. That cylinder either had to be in the “accessory” position or the “unlock” position, don’t remember which. On many Fords, you turn the key to the “on” position and insert a 1/16" punch or other slender object into the smallest hole underneath the lock cylinder to press a release button. No disassembly required whatsoever.

No friendly mechanic friends around to help you?

We have lost the OP.