Stock Lift Measurement?

I just bought an '83 CJ7 that currently has 33x14.5x15 MT Baja Belted HP tires. The tires are rough riding at speed and old so need replacement. I may go down to a 31 since I won't be doing anything extreme enough to require that aggressive of a tire. However, the current owner knew nothing about the lift modification done to this jeep. Lift charts indicate that a 4" lift would have been required to fit the current tire. For my info, how can I determine the amount of lift that has been installed? Does anyone have a stock frame-to-axle, frame-to-ground or some other measurement I can use to determine the added lift?

The PO's did not adjust the speedometer to match the tire change so that's something else I will have to handle. Back in the old days (I'm 67) we would run two cars together to find the difference. Later we would do about 10 measured miles with the mile markers on the interstate. It just occured to me that today's GPS units give you the speed (they're even making gps speedometers these days) so I just need to plug one in, run to 60 mph on the GPS and see what the speedometer is reading.

 

I am afraid pics of your jeep will be needed if you can post one. There is more than one way to fit 33's under a cj, but 4" is about right for 33's. You could have 4" lift springs, or you could have a smaller lift such as 2 1/2" with trimed fender openings, extended shackles, body lift with your smaller lift springs. As an example, I am running 35's on a 2 1/2" lift with a small body lift and trimmed fenders. So it is hard to say if you are using 4" springs and a picture would tell all. You can fit 31 on the stock suspension, My brother had 4" springs and 32's on his cj and it looked really nice.

 

In doing some searches I get the following:
Stock with 30" tires:
69.3" overall height
20" to bottom edge of body at driver's door.

My numbers are ~72" and 23". I think the actual OD of the 33x14.5x15 tire is ~32.5". Not much air and on dirt so maybe 16" to hub center vs. 15" stock. So maybe 1"+ from the tire.

Generally looks like a 2" lift. Body is down on frame front and rear so no body lift. I would probably need this to determine replacement shock absorbers and I bet there's lot of folks that don't know their lift but need to.

Comments?

 

It is very hard to guess on this.
your springs may have been on there awhile and have sagged some which will throw off the measurement you have taken, body lifts (which you say there isn't one), longer shackles, ETC.. You can run a 33" tire on both a 2 1/2" lift and a 4", in general though a 2 1/2" will not require a drop pitman arm, or extended brake lines, or t-case drop, or shims for the rear springs so your u-joint angle isn't as steep. If these things are not on your jeep, it would be my guess that you have a 2 1/2" lift, but there is no garentee. you can run a stock length shock on a 2 1/2" lift. I would get longer brake lines even with the 2 1/2" lift, thats just me, they are not suposed to be required though. If you can post a picture of the jeep, Im sure their are several people on here that could tell you right off the bat what lift is on it.
I did measure mine from the ground to the bottom of my door and it is 24 3/4" on 35" tires

 

Here's my new to me '83 CJ7:

 

thats 2 1/2" lift. If you go any bigger at all, you will be hitting the lower corner of you fender when the tire stuffs up in the fender opening. Your wanting to go smaller, so your fine. They seem to be hard to find anymore, but I used to like to run a 32X10.50, it gave a decent ride and added a little more height for off road. 31's are a good choice too.
Oh, NICE LOOKING JEEP TOO.!!
You say that it rides rough. check your shackle bolts that they are not too tight. If they are tightend to much your suspension can't move and will result in a very stiff ride. I have installed many leaf springs on cj's and found the torque specs to be useless. Make sure the shackles move feely when you stand and bounce on the bumpers, if not try backing the nuts off about a half turn and try again. Of course check them from time to time.

 

Thanks, jeepcj! That's about what I figured. I'm looking at going to 31x10.5 on the tires. Current rims are 10" so I plan to go down to 8". I paid $4800 for it. 500 miles on engine rebuild and new trans according to PO. A little rust at base of windshield and bottom of rocker panels but otherwise in excellent shape. I need to get several of the gauges going again. Seems to be a problem on the power supply side. CJ7s are plentiful here in south central Texas. Mainly I just need to configure it to my tastes. Thanks for the suggestion on the shackles. I'll see how it does after I get rid of the big flotation tires.

 

Yeah, a 10" rim is a little too wide for 10.5 tire width. 8" are perfect. I know what you mean about the flotation tires, I have 35x14.50s and they are just too wide. Im going down to 12.50s when its time. good luck with you jeep!!!!