Has anyone used RennStand Jack Stands on their C8? If so what adapter did you use?

JT

 

^^^
FWIW, Member Strake used those when changing brake pads. I noted his pic and mentioned his name in my PDF on "How To" change C8 Z51 brake pads where most removed the caliper. As I recall he later bought more expensive, electric powered Quick Jack. Might PM him.


More recently Member Big Lebowski showed his simple, far less expensive method. Also detailed with his name referenced in my How To PDF: http://netwelding.com/Ceramic_Pads.pdf


After looking at his approach, realized you could use jacks with jack pads in GM designed oval slots and put a small base jack stand close to the oval slot, even closer than the round hole using a wood etc pad on the frame. Then no need to modify the jack pad to fit a round hole. If careful there will not be a tipping issue. Frankly I use two jacks and jack stands jacking each side alternately several times as I raise the car. Same as I have on my C7s. I keep slight tension on the jacks after lowering on the jack stands for extra safely.

Big Lebowski's small base jack stands are a bit expensive (BUT NOT Nearly as expensive as RENNSTAND.) I bought a small base jack stand from Walmart for ~$10 that could do the job.

 

I have the standard HD jack stands (like the red ones in your photo) and used them on my C5 many times but the C5 has multiple places to jack at the front or back and I put the jack stands under the tie down points... I'm considering the Quick Jack as well.

JT

 

^^^^
Here are some other less expensive ways FWIW.
My two-jack method has worked for me. As mentioned, I always jack each side, alternating from one side and the other. Then lower on my jack stands keeping the jacks with slight tension as a safety and adding stability. The other thing I do when needing back and front in the air is to follow the safety advise mentioned on one of jack stands Warning Label. Never use jack stands rear and front. I made my wheel stanchions (but can buy) and use under one set of wheels. They are light and take little space.



Made my wheel Stanchions from wood.


I always follow the Warning on one pair of my jack stands: ONLY USE ON ONE END. Not stable enough for me to get under may car supported by jack stands front and back!


BTW have commercial wheel stanchions I used when building my street rod. But they are 12 inch high and take a twostep jacking process to get that high. Was fine when I had the rod on all 4s installing wiring, exhaust, trans cooler etc etc. I spent a month on my mechanics creeper and it as very safe. Don't need the C8 that high. Quick Jacks would be in the way.

When installing side skirts that are riveted to the rocker panels just used my wheel stanchions after jacking using the GM oval jack pad slots. Nothing in the way.

 

Depending on your jacking pucks, I would use the “Universal Crown / Castle Jack Pad for RennStand (18M-P05)”. My jacking pucks are 2.5” wide and 1” tall so they would fit inside the “cup” of that adapter. It looks to me like the Corvette specific adapter (C8 isn’t listed) is too wide on top, at .75”, to fit into the lift point slot. The piece on my jacking puck that goes into the slot is only .5” wide, it looks to me like the slot is only about 5/8” wide, I don’t think the .75” part of that adapter will fit into the slot, although I could be wrong.

Don’t forget that you are going to have to jack up the car and put the tires on blocks first before using the Rennstand. This will be necessary in order to fit the floor jack, Rennstand crossbar, adapter and jacking puck all underneath the car. I built some wheel cribs similar to @JerryU, but mine are made entirely of 2x4s. They are 9” tall and are fairly heavy, but they won’t fail! Picture below.

When using my JackPoint jack stands I still need to lift the car and set the tires on a 2x4 first in order to fit the low profile floor Jack (3.5”), flat JackStand adapter (.75”) and jacking puck (1”) under the car. The car is very low, I only have about 5” of clearance on my factory height non-Z51 HTC. I could probably simply drive up onto a 1” piece of plywood and get enough space, but the few times I have needed to lift the car I have just just jacked it up, slid a 2x4 under the tire, set it down on the 2x4 and then proceeded with the JackPoint jack stands.

 

Here is a pic of my RennStands, safe jack. I use a typical corvette jacking puck on top of it.

 

Does Safe Jack sell those stands anymore? I looked at their website and did not see anything like that.

 

Not sure. I've had mine for about 3 years now.

I found this on their site; www.rennstand.com/product/rennstand

 

At the time I owned a set of RennStands for my former C7 and then C8........ until I sold them and bought a QuickJack lift, I used an adaptor plate on top that had a round pin welded to it on both sides of a round disc. The one pin went into a hold on the top horizontal bar of the RennStand, and the opposite side pin went into the Jacking Puck Location hole on the frame of the C8.

I'm pretty sure this is what adaptor plate I used....

RENNSTAND JACK PAD COMPATIBLE WITH CORVETTE / RANGE ROVER (18M-P18)

It was a really nice product, (RennStand), although somewhat pricey..... but you could jack up your car in the correct location and at the same time put your jack stand in place all in one motion.

 

@Strake I also have that adapter but used it to lift my porsche. Never thought to use it on the C8 at the puck locations.

 

Considering these as well, but concerned about the stability, when it is being raised one at a time, against the jacking puck, that is already on the car.

 

^^^ I found these to be very stable and had no concern for the opposite side tipping over or slipping out of the hole in the frame. I did NOT use these against a jacking puck as the adaptor plate on top acts as a puck by itself and has a pin on top that goes into the hole in the chassis. I would NOT feel comfortable if I was trying to use it against an already installed puck with a smooth surface on the bottom.

My reason for going away from this to a Quick Jack was that I wanted to be able to raise all 4 corners of the car and I only had 2 of them. I would need to buy 2 more. With the price of these with adaptors for each one it was about $1k. for a set of 4. For a bit more, I was able to order a QJ and it was a lot less hassle for me to quickly raise the entire car up. Sold the RennStands here on the forum.

 

@promethius I have two stands and typically left one side or one end of the car. I would not put a car on four of these stands at one time.

I have a scissor lift that I've used for my C5 but can't use with the C8. I have a quick jack on order for lifting the C8.

 

Yes, that is all I was considering, is either one side or one end with two of them. But still concerned about it slipping off the puck, when you are trying to do the other one, either across from it or on the same side.

 

^^^
Yep when doing things like removing and installing exhaust where a lot of force is required, only way I felt safe is using 4 wheel stanchions! Quick Jack may be OK is not in the way.


When building my Street Rod only felt safe installing exhaust etc with all 4 wheels up on my 12 inch high commercial wheel stanchions. However took a two step jacking process and was only worth the effort when car was up for over a month and I was on my mechanics creeper! Still have but now use my two lower homemade wood stanchions.

 

Received the above part today from Rennstand. The diagram says the part is .75 inch in diameter. Mine measured out at .63 . I measured the car oblong hole as being able to take

up to a .71 inch diameter '"plug"