Monroe 58617 Shock + Pro Comp 13120 Leaf

[Saturated Fat]

Hello guys. My '99 Explorer, Zoosy, is in need of a butt lift. Below you will find what Zoosy looks like. I had the Monroe 58617 installed in another '99 Explorer, Jeffrey, but the result was pretty much meh. It rode great with the Monroe, but still looked bland.

I am wondering if it would be practical to install both, the Sensa-Trac and the Pro Comp AAL. Would there be any discernible ride height difference if I went with both? I know the Sensa-Trac makes the ride a little bit stiffer, so would the combination of the aforementioned AAL and the Sensa-Trac give me Bleeding Piles?

I have tried searching around here for any similar topic, but I seem to be the only one with this query. Therefore, any help will be appreciated

 

[ZWilson07]

It shouldn't be to bad but again this is going to depend on what kind of ride you are used to. A ton of people run a shackle in the rear.

It will definitely be a reasonable difference in the rear height.

 

[Saturated Fat]

Thank you for your reply. Unfortunately, I would never consider shackle lift for anything that travels on highways.

Basically, I want to know if the ride will be stiffer than SensaTrac-only setup

 

[ZWilson07]

Thank you for your reply. Unfortunately, I would never consider shackle lift for anything that travels on highways.

Basically, I want to know if the ride will be stiffer than SensaTrac-only setup

I would say the sensatrac only setup will ride a little better. Theres no two ways around it, that adding another leaf is going to make it stiffer but to be fair I don't really think there will be a "huge" difference. At the end of the day these are 10 plus year old suv's so they aren't going to ride good, but again like before, this is going to depend on what you are used to.

My 1990 F250 4x4 diesel with 45,000 original miles I felt rode damn great for a 25 year old truck with factory original parts. Impressed me every day I drove it (Hell even better than my 06 Dodge 3500 2wd which just plain sucks in the ride department). That same truck to someone else would have been terrible and you couldn't even pay them to daily drive it. So a 100% truthful answer is, it is all just going to be relative to that particular person in my opinion.

Personally running an aal in the rear with new nice shocks isn't going to be "much" of a difference when compared to stock springs with sensatracs. Of course an aal with ****ty shocks might be noticeably worse or the aal/sensatrac combo might be just enough to go over that tolerable mark. There are just so many variables for one person to truly know for sure. I wouldn't stress out to much over it.

If I was wanting a little lift for some bigger tires or new wheel/tire setup, I would do rear shackles or aal with nice shocks, crank the torsion bars a little and roll on. If I was just going to keep a stock run of the meal setup and use it for the normal occasional Lowes/HD run, then probably just run the sensatrac only route. For me, I will be going rear shackle or whole spring replacement with very nice shocks and coilovers up front. I rocked 30's/31's/32's/and 33's on torsion bars for years as a daily driver and I am finally done with it.

 

[Saturated Fat]

Thanks for the prompt late night replies! Really appreciate that.

While reading your post I realised that I could always become a mule for that kind of setup since no one here is running it Afterall, it takes pea amout of work to put on or take off the leaf.

The Pro Comp 13120 is going for $36 shipped on Amazon. Might as well get it and post my findings here. I'll take them off if I don't like them.

Thanks again for the prompt and informative replies

 

[ZWilson07]

No problem. I work night shift during the week so unfortunately my weekends don't magically change. Makes it really rough on me when getting up for church on Sundays and being up the whole day but I guess at least I have a job lol.

Look forward to seeing how it works out.

 

[Saturated Fat]

Thanks again!

 

[ZWilson07]

Thanks again!

You're welcome.

 

[SoNic67]

My experience with Sensatrac was that they suck. I took them off my truck almost immediately (first the rear and then the front).
First of all, in order to work properly, they require an exact OE ride height because they are positional-based. My rear sags just enough to place the off their correct position.
Second of all, in my short usage of the fronts I managed to blew the seal on one of them, it was completely limp when I took it out. Not off-roading, just on paved streets!

I replaced them with single-tube shocks, because they are, IMO, the best shocks that you can buy (except the hydro-magnetic ones). As proof - you can find them in all high-end luxury vehicles.
I choose KYB Gas-A-Just because a balance of price and quality. They ride almost like a car on bigger humps on the road.
For small potholes, cracks they can't do nothing, that's where the tires are needed. I put Michelin and they are 100% better that the OE tires that I had before.

As for the rear sag, there is no way around it - you need either a 1" larger shackle or new leafs. Adding anything else on their spring rate (to raise the rear) will just stiffen the ride compared to OE setup. That's just physics 101.
Your add-a-leaf will do exactly that. I know somebody with that setup, the rear is hard as rocks, basically the shocks are canceled by increased stiffness.

In the end... short of putting coils on rear (like 2002+ models) there is only so much you can do.

 

[my98nnj]

I choose KYB Gas-A-Just because a balance of price and quality. They ride almost like a car on bigger humps on the road.
For small potholes, cracks they can't do nothing, that's where the tires are needed. I put Michelin and they are 100% better that the OE tires that I had before.

100% correct ^^^^

 

[Varsity]

I have a lifted truck a little more off-road geared but I figured I'd share whatever experience I have.

I have the Monroe Sensa-Tracs as shocks and I also have a Pro-Comp Add-A-Leaf in the rear. I had the Sensas on my truck for awhile before I lifted it and found the ride to be pretty good. It probably didn't help that the shocks I had on before were totally shot, so of course anything would be an improvement. It was a very firm ride, but it's almost exactly how I'd expect a 10+ year old SUV to ride. Not bone-jarringly painful, but definitely no Cadillac ride. That was quite a few years ago, so my memory is a bit fuzzy, but I'd say they are halfway decent shocks. Are they the best? Probably not, but you could do a whole lot worse.

I also added the Pro-Comp add-a-leaf to my new 4-door leaf springs when I lifted the truck. In my opinion, the add-a-leaf and new leaf springs barely made a difference on ride quality, but since I changed so much stuff back there, I guess I can't really say anything.

All in all, even with a lift and 33's, I'm running street Sensa-Trac shocks with new leafs and the add-a-leafs and I find the ride pretty decent for what is basically a truck suspension. Most of the people who ride in my truck have no complaints of roughness, so I'd say the whole added stiffness part of the shocks and stuff is a little exaggerated at times, in my opinion. I can't really say what effect it will have on a stock vehicle.

 

[Saturated Fat]

Thank you guys!
Since I already have some 250 miles old Sensa-Trac from Jeffrey-the-truck that I sold less than a month back, I'm now thinking about putting those along with...Warrior 153 shackles. Would I require a camber kit after I am done TT'ing the front to match the said rear?

 

[SoNic67]

I have a lifted truck a little more off-road geared but I figured I'd share whatever experience I have.
I have the Monroe Sensa-Tracs as shocks and I also have a Pro-Comp Add-A-Leaf in the rear.

You probably don't know how bad those are on your truck, you just assume it's normal.
Sensatracs have 1-2" of "comfort" damping on center of the excursion. You lifted the suspension, so now your "at rest" location is in a different part of the shock ( because is extended).
Now you have a harsh ride on asphalt with small bumps, but when the bump is larger (compressing the shock), suddenly the shocks arrive in the "smooth" position - so now, when you would need a stiffer shock you have a "loose" one.
So basically you bounce all over the place on large bumps, but you have a rocky ride when street is smooth.
What's even worse is that it is asymmetrical - compression bounces will act different from the extension ones.

See this:

 

[swshawaii]

^ Here's Monroe's technical training page.
http://www.monroe.com/en-US/support/Technical-Training/Shock-Absorbers/

Appears Monroe has renamed the SensaTrac to OE Spectrum using identical part numbers.
http://www.monroe.com/en-US/products/OESpectrum
http://www.monroe.com/en-US/catalog/e-Catalog/58617

 

[Varsity]

You probably don't know how bad those are on your truck, you just assume it's normal.
Sensatracs have 1-2" of "comfort" damping on center of the excursion. You lifted the suspension, so now your "at rest" location is in a different part of the shock ( because is extended).
Now you have a harsh ride on asphalt with small bumps, but when the bump is larger (compressing the shock), suddenly the shocks arrive in the "smooth" position - so now, when you would need a stiffer shock you have a "loose" one.
So basically you bounce all over the place on large bumps, but you have a rocky ride when street is smooth.

I don't doubt any of that. I know my ride could be much better, but I've had much much worse, lol. Like I said, they seemed fine before I made any modifications. When I lifted it, I said screw it and left everything the way it was cause it seemed comfortable and fine for me. I wasn't going for a luxury cruiser ride anyways. I'm the only one who drives it and hardly ever have passengers so I figured I would at least try to get some more mileage out of them before replacing them.

If the ride starts to get painful or I notice odd tire wear patterns, I'll change them immediately, but after ~25k miles, nothing yet. I want to get at least a year more out of them before I get something a little better. I figured the Sensas weren't the best for my current situation, I was just mentioning that for the couple of years my truck was stock, I had no complaints with them.

 

[Produce Man]

You probably don't know how bad those are on your truck, you just assume it's normal.
Sensatracs have 1-2" of "comfort" damping on center of the excursion. You lifted the suspension, so now your "at rest" location is in a different part of the shock ( because is extended).
Now you have a harsh ride on asphalt with small bumps, but when the bump is larger (compressing the shock), suddenly the shocks arrive in the "smooth" position - so now, when you would need a stiffer shock you have a "loose" one.
So basically you bounce all over the place on large bumps, but you have a rocky ride when street is smooth.
What's even worse is that it is asymmetrical - compression bounces will act different from the extension ones.

See this:

Nailed it Sonic. Some here continue to believe the SensaTracks will work. As designed for primarily for towing, the shock takes the added load and enters the comfort mode-perfect for highway towing. You just get a little lift with zero or little ride quality improvement.

 

[chefduane]

My experience with Sensatrac was that they suck. I took them off my truck almost immediately (first the rear and then the front).
First of all, in order to work properly, they require an exact OE ride height because they are positional-based. My rear sags just enough to place the off their correct position.
Second of all, in my short usage of the fronts I managed to blew the seal on one of them, it was completely limp when I took it out. Not off-roading, just on paved streets!

I replaced them with single-tube shocks, because they are, IMO, the best shocks that you can buy (except the hydro-magnetic ones). As proof - you can find them in all high-end luxury vehicles.
I choose KYB Gas-A-Just because a balance of price and quality. They ride almost like a car on bigger humps on the road.
For small potholes, cracks they can't do nothing, that's where the tires are needed. I put Michelin and they are 100% better that the OE tires that I had before.

As for the rear sag, there is no way around it - you need either a 1" larger shackle or new leafs. Adding anything else on their spring rate (to raise the rear) will just stiffen the ride compared to OE setup. That's just physics 101.
Your add-a-leaf will do exactly that. I know somebody with that setup, the rear is hard as rocks, basically the shocks are canceled by increased stiffness.

In the end... short of putting coils on rear (like 2002+ models) there is only so much you can do.

My experience was a bit different. I've been very happy with the Sensa-Tracs. I got about 1" to 1-1/2" of lift, so no more butt sag. I've had them on for about a year and a half now and am very satisfied. They do have a little stiffer ride but I am the only driver and really don't care or expect a 17 year old truck to ride like a couch. So far no leaks, blown seals, or anything like that. They were a good choice for me , my truck, the way I drive, and my budget. That's about all one can ask, eh?

 

[SoNic67]

^ Here's Monroe's technical training page.
http://www.monroe.com/en-US/support/Technical-Training/Shock-Absorbers/

No, it still "Primarily aftermarket under the Sensa-Trac brand name". The PSD (Position Sensitive Damping) is older technology, no wonder everyone switched to ASD (Acceleration Sensitive Damping) now - including Monroe that now has the Reflex line with ASD.
Monroe introduced the PSD in 1991 (Sensa-Trac) and in 1999 they introduced ASD (Reflex). In 2005 they introduced Monotubes (labeled Reflex Monotube): http://www.monroe.com/en-US/about-monroe/Monroe-History/

However, Monotubes are a step better in shocks (basically the high-pressure nitrogen acts like a air spring at fast movements). No wonder that all the luxury vehicles employs some kind of monotubes for their shocks.
Because the area below the dividing piston is pressurized to about 360 psi with nitrogen gas, this high gas pressure helps support some of the vehicle's weight.

Like I said, one need to replace the shocks to feel the difference. They go bad so slowly that you get used to the bad ones. I see daily cars and trucks on HW that are bouncing all over the place and their drivers seem to be oblivious to that.
On Explorer there will be no tread wear warnings either, only on small cars you see that (McPherson).

 

[swshawaii]

SensaTrac is nowhere to be found on Monroe's web site. OE Spectrum is the same shock and part number with a different name.

http://www.monroe.com/en-US/products/

 

[SoNic67]

Hmmm, those are Impact Control Valve (ICV) - definitely not PSD (SensaTrac). I would say is a rebranded Reflex line.
The e-catalog was updated last on 02-01-2015 and looks like the SensaTrac is out of their production!
Not a second to early IMO....