Verifying Rancho shock part numbers

Irun

Irun

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A buddy just installed Currie 4" lift springs on his LJ and wants to run Rancho RS5000X shocks. I've not run them myself and understand they run a little long. Normally I'd measure for shocks, but don't have access to his Jeep (He's several states away). On his setup he has no body lift, so are these the correct part numbers, RS55255 and RS55256?
 
Those are the part numbers I used for mine with a 4" and 1.25" body and can use all the uptravel. The 5255's were on sale cheap on rock auto about 2 weeks ago IIRC. I still have to play around with CA lengths but they seem just about right.
 
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Morks said:
Those are the part numbers I used for mine with a 4" and 1.25" body and can use all the uptravel. The 5255's were on sale cheap on rock auto about 2 weeks ago IIRC. I still have to play around with CA lengths but they seem just about right.
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Same here.
 
Morks said:
Those are the part numbers I used for mine with a 4" and 1.25" body and can use all the uptravel. The 5255's were on sale cheap on rock auto about 2 weeks ago IIRC. I still have to play around with CA lengths but they seem just about right.
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PNW_LJ said:
Same here.
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He doesn't have a body lift. How much uptravel do you both have with one?
 
Travel wise in the front I have 4.75" up and 3.75" down (passenger) and 6.35" down (driver). I was in a rush doing that side so I am not sure if that 6 down is super accurate. The track bar was the limiting factor. For the rear I have about 3.87" up and 5.12" on both sides.
 
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I use the 55255 and 55256 with 4" Currie springs in the front and some unidentified in the rear that probably sit a bit lower than Curries. I do have a body lift but that doesn't really change much. The next shorter part number would leave him way off of 50/50 and maybe like 3" or less of down travel. Mine is 4.9 up and 5.8 down in the front, and split evenly in the rear.
 
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@Irun you’re correct. I installed a 4” RockJock lift this summer and used the RS55255 and RS55256 shocks. I called Rancho to confirm also before I order them. I didn’t measure before ordering, as I didn’t know any better. I’m still learning this Jeep stuff, as I’m only 6 months into it. I don’t think a body lift would make difference with the RockJock kit. I do have a 1.25” BL.

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Irun said:
He doesn't have a body lift. How much uptravel do you both have with one?
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Up front, my bumps are set for shock compression and I have a 50/50 travel split. I’m guessing most people are going to be getting something similar.

I have some strange things going on in the rear with my setup (6up/2down), but that shouldn’t apply to other setups.
 
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freedom_in_4low said:
I use the 55255 and 55256 with 4" Currie springs in the front and some unidentified in the rear that probably sit a bit lower than Curries. I do have a body lift but that doesn't really change much. The next shorter part number would leave him way off of 50/50 and maybe like 3" or less of down travel. Mine is 4.9 up and 5.8 down in the front, and split evenly in the rear.
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What lengths are your lower control arms set at both front and rear? Trying to dial my suspension. I know my fronts are definitely too far. When I stuff the front tire it goes way too far to the front of the fender and makes contact with my track bar at full bump.
 
Morks said:
What lengths are your lower control arms set at both front and rear? Trying to dial my suspension. I know my fronts are definitely too far. When I stuff the front tire it goes way too far to the front of the fender and makes contact with my track bar at full bump.
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I'd have to put a tape to it but it wouldn't necessarily be a true setting for yours. I start (with the frame on stands and springs out) by stuffing the axle all the way up to the bump stops, then adjust the arms to put the axle where it needs to be...which is as far forward as I can get it without track bar contact. The driver side is where the track bar is so I set that one where I want it and just set the passenger where it needs to be to square the axle.
 
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freedom_in_4low said:
I'd have to put a tape to it but it wouldn't necessarily be a true setting for yours. I start (with the frame on stands and springs out) by stuffing the axle all the way up to the bump stops, then adjust the arms to put the axle where it needs to be...which is as far forward as I can get it without track bar contact. The driver side is where the track bar is so I set that one where I want it and just set the passenger where it needs to be to square the axle.
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Yeah just trying to gauge. Thought I had it alright until full bump and it touched the track bar. It was hot and I needed it for work the next day so buttoned it up and haven't gotten to it since. Hopefully in the coming weeks I can finally get to it. My fronts are sitting at 16.5" so long from what I am seeing on the forum.
 
Morks said:
Yeah just trying to gauge. Thought I had it alright until full bump and it touched the track bar. It was hot and I needed it for work the next day so buttoned it up and haven't gotten to it since. Hopefully in the coming weeks I can finally get to it. My fronts are sitting at 16.5" so long from what I am seeing on the forum.
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RockJock recommends starting @ 15 3/4” c2c for their lowers with a 4” lift. I started there when I installed their 4” lift, my stops were dang near centered and I had no clearance issues.

After checking my stops were centered, I squared the axles to center skid bolt. If I remember right, my passenger LCA needed extended around an 1/8” to be squared to the skid bolt and subsequently the rear axle, which I did first. That measurement to square it, will most likely be different for you.
 
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rows said:
RockJock recommends starting @ 15 3/4” c2c for their lowers with a 4” lift. I started there when I installed their 4” lift, my stops were dang near centered and I had no clearance issues.

After checking my stops were centered, I squared the axles to center skid bolt. If I remember right, my passenger LCA needed extended around an 1/8” to be squared to the skid bolt and subsequently the rear axle, which I did first. That measurement to square it, will most likely be different for you.
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Definitely a great starting point from where I was at before. For now it works, but would like to do some way harder trails come next year when it'll be more important. Thanks!
 
Morks said:
Definitely a great starting point from where I was at before. For now it works, but would like to do some way harder trails come next year when it'll be more important. Thanks!
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If I remember correctly I started with Rockjocks baseline and went from there.
 
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