Easy conversion for liftgate slides to gas shocks!!!

[Hart_Rod]

I have never liked the slides hinges on my liftgate and have been wanting to convert it to gas struts since I bought my 69 Burb a year and a half ago. I kept putting it off because I thought it was going to be complicated and time consuming. I figured I would have to modify the attachment points and wasn't sure how that was going to work. Well, yesterday, I removed the ball studs that hold the gas pedal on because I am running an elctric pedal with my 5.3/4L60E conversion. After I took them off, I decided to see if they would work for mounting points for the gas struts. They just so happen to be the same size threads that screw into the liftgate and tailgate attachment points! Now all I had to do was figure out the compressed and extended length of the strut. With a little bit of measuring, I came up with a maxium compressed length is 13 1/2". The extended length need to be around 21" in order to get the correct height on the liftgate. Armed with some measurements I went to Advanced Auto Parts and started going through their Strong Arm gas strut catalog. I finally found one that I thought was close in length and lifting force and bought it (#4248). This first strut worked well as far as clearance and lifting force, but it didn't quite raise the gate up high as I wanted. So I started looking on the internet and found this site:

http://www.autopartsbylou.com/auto-parts-search.php

After some searching I found another strut (#4220) that was a little bit longer and about the same lifting force. Another trip to Advance and I had 2 of the longer struts. They work great! Plenty of height and plenty of lifting force. Probably one of the easiest conversion I've ever done. I love it when everything falls into place, I guess I should've done this sooner!!

This project can be completed in about 30 minutes and it works great. Here's all the stuff you need to make the conversion:

1. (2) StrongArm gas strut (part #4220), or equivalent (these are made for a 1985 Volvo 740 hatchback). I got mine at Advanced Auto Parts @ $25 apiece and have about 76 lbs of lifting force. Ones from a 1997 HONDA CR-V are the same length but only have 44 lbs which might work on the Blazers.

2. (4) of the ball studs that are used to mount your gas pedal to the floor

3. Phillips screw driver

4. 1/2" wrench

First, use the phillips screwdriver to remove one of the slide hinges. Next, thread one of the gas pedal ball studs into the top hole that holds the slide hinge on the liftgate (use the 1/2" wrench to tighten it). Then thread one of the ball studs in the bottom hole that holds the slide hinge on the Burb body (use 1/2" wrench to tighten it). Next, pop the gas strut in place at the top and the bottom. I'm not sure if it makes a difference which way these are attached, but I looked at my 2003 Suburburan and it has the cylinder at the top and the extension arm pointing down. Repeat for other side and you are done!!! Probably one of the easiest mods you'll ever do.

P.S. In the last photo, I also added cable straps to my tailgate in about the same amount of time. Cables came from EBAY:

http://cgi.ebay.com/ebaymotors/CHEVY...QrdZ1QQsspagen

[Hart_Rod]

Originally Posted by suville

What are the cables from?

I got them off of Eeebbbiillllll Bay!

http://cgi.ebay.com/ebaymotors/CHEVY...QrdZ1QQsspagen

http://cgi.ebay.com/ebaymotors/68-91...spagenameZWDVW

[Hart_Rod]

Originally Posted by Frizzle Fry

Too easy!

Who would have thunk it! It took me longer to get the ingition cylinder out, . I finally took a big hammer and screw driver to it, .

One thing I forgot to mention, with those struts, the liftgate doesn't open quite as wide as it did before, but I think it will work fine.

Rob

****** Corrected in top post!!!****

[Hart_Rod]

OK guys, I've already found an improvement for the strut conversion. I wasn't really happy with the height that the first struts were giving me, so I kept looking until I came up with this. These struts are off of a 1985 Volvo 740 Hatchback (Strong Arm part #4220). It is very close to the original height of the liftgate. The first picture below is with the first strut I tried. The next two pictures are the new strut. Let me know how the conversions come out.

Rob

[Hart_Rod]

Forgot to ask, is this bolt for suburbans with barn doors to prevent them from swinging open to wide??

[Hart_Rod]

Originally Posted by cstanley

that's an awesome mod! i'm gonna do this to the blazer...

can you get the round-headed bolts off the shelf?

also, is there a way to get inside the blazer hatch to replace the metal backing plates at the mounts?

CStanley - You probably can get the bolts, but I'm not sure where. I'm not familiar with blazer hatch. I'm sure you can do this but you will probably have to do some fiberglassing. You will want to use a different strut though, these provide about 75 lbs of lifting force apiece. I'm sure you could get by with half of that on the Blazer since it's fiberglass. Here's a link to the site that helped me figure out which strut I wanted to use. It let's you choose the extended and compressed lengths, and then tells you the particular amount of force provided for the one you picked out. It took me a while searching, but it wasn't that hard.

http://www.autopartsbylou.com/auto-parts-search.php

[Hart_Rod]

Originally Posted by Long Roof

It looks like you switched holes for the longer strut. Just to be clear which holes are you using in the hatch and body for mounting the struts? I am assuming you are using the holes that are furthest apart.

Aaron

That's correct, I moved up to the top hole in the liftgate and still using the bottom hole on the body. I re-wrote my original post with all the updated info. Let me know how it come out.

Rob

[Hart_Rod]

Originally Posted by gregfull

As I said in a PM earlier, great mod Rob. I have attached a link where I buy alot of hardware for our shop. They have the struts, and the ball joint fittings. They even have the struts in stainless...bling, bling. Pretty pricey though. Here's the link, they start on page 1097 or do a search for gas struts. http://www.mcmaster.com/

Cool site Greg!!!!

R

[Hart_Rod]

Originally Posted by cstanley

not sure how much the blazer hatch weighs, but the existing strut is ~12" compressed, ~18" extended. i hunted on that site, and it came up with something like 126lbs?!

Can you take a picture of the Blazer attaching points?

[Hart_Rod]

Originally Posted by jmbstudios

I have a 72 Sub and the gas pedal is not mounted to the floor, so I will need to buy some ball studs.

Which ones are the correct size for this application??

thanks
jeff

Jeff,

I didn't realize that 71-72 trucks had a different pedal.

GMC Pauls lists them as gas pedal studs part # 522825. You will need 2 sets.

http://www.gmcpaulstruckparts.com/pe...ds_&_misc1.htm

[Hart_Rod]

Originally Posted by Burbinite

These only hold 30lbs each but are much cheaper! I haven't taken my fishin' scale to the liftgate but I think 60lbs of force should keep it up??

Just my $.02

http://www.surpluscenter.com/item.as...6&catname=misc

I think that one will be to long. It says it has a 14" compressed length and I think 13 1/2' is the longest compressed lenghth you can have and still use the original mounting points. As far as the lifting force, when I only had one 65lb shock on, it would hold it up but not to its fully extended height. At that price I guess it's worth trying.