04 Dodge Ram 1500 lift kit problem

I just installed the 2002-05 RAM 1500 4WD 6? PERFORMANCE SYSTEM made by Fabtech and put 35x12.5 BFG MTs and 17x9 MT classic II rims (see pic here:

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and
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). and I have 3 major problems:

1). I had the truck aligned before installing the lift (according to lift instructions) and all was fine. I installed the fabtech lift and the truck is now pulling hard to the right. I had the Dodge dealer align the front end and it is still pulling to the right. I returned it to the dealer and had them verify and it is within (factory) specs. Did the fabtech lift change the specs on the camber, caster, and/or toe? I will contact Fabtech directly about this, but I doubt they will admit to it. I think they would have included this in the instructions if the specs changed, right? If they can't supply the new specs - how do I correct the problem? Can I get a shop other that the dealer to align the truck without using factory specs - or - is there no place to start then?

2). I have a vibration at 40-60MPH that is not very nice. (no changes were made to the rear drive shaft, etc....)What components could cause this? I had the tires balanced and they used the stick on lead weights inside the rim. Are tires this big able to be balanced like that? I thought there was something that goes inside the big tires that balances them.

3). I had the dodge dealer recalibrate the computer / speedometer to compensate for larger tires. Now the cruise control only works up to 45MPH (I can only turn on cruise below 40 MPH and then using the buttons on the steering wheel accelerate up to 45MPH before it shuts off). Again, I returned it to the dealer and they says it's not the computer recalibration. They have never heard of the problem. I know it has something to do with the big tires and the computer recalibration, because the cruise worked fine just before the recalibration.

Any help or advice would be appreciated.

Reply to
HomeBrewer
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It will change the caster which can effect directional control and bear in mind that the front end was NEVER disigned for the added stress that this adds to vehcile some there will be issues. Have dealer print out alignemnt setting on vehicle now and I can tell you what to do because factory spec co out the wind with a lift. If you want it to track right you will need to do some tweaking here.

With heavier and larger rotating masses it is harder to balance plus ujoints in drive shfts are not constant velocity and they can cause vibration at higher angle and the higher tourqe load on them from much larger tires with stock gear makes it even worse.

You need more the a speed calibration here. YOu effectively made your final drive ratio about 2 steps taller and through in bigger tire drag and your drive train will work a lot harder and your RPM is lowr at 40 than before becausethis (it is equal RPM wise to about 32 before the lift) To fix this and make truck run a lot better you need at least

4.56's and 4.88 would be better still them recal speedo and such and you will get what you are looking for and longer driveline life with much better performance too.

----------------- The SnoMan

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Reply to
SnoMan

Camber and Caster are the angles that would cause a pull toe in wouldnt. i would further check to make sure the rest of the of the suspension is tight. take it to a requtable front end shop. sounds like your going to need quality, qualified professional help on this one.

my first guess would be that you have changed your driveline angles. your u joints may be running at too high of an angle. its not a big deal if you know what your doing. but thats the thing you need to know what your doing here too.

sorry cant help you on this one.

your welcome, hope i've been of some help.

Reply to
Chris Thompson

Actualimproper toe in with a improper camber can indeed pull as iot can aggrevate it. ANd again, stock alignment spec tend to be a starting point with a lift, not the final word because the stress on front end (which does actually flex some) has all changed with a big lift with oversized tires. (it changes the load center relative to axle pivots and the forces the road transmitts back to steering axle relatie to them)

----------------- The SnoMan

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Reply to
SnoMan

All fasteners were re torqued to specs after 100 miles...everything is dead on. I switched front tires from side to side and it still pulls right slightly. Seems to be less than before the switch tho.

The lift was designed to keep factory drive line angles, the front diff was dropped to compensate, the rear was only lifted ~1" using helper springs, there is no stress on any of the u-joints. I think the vibe is tire related now.

Reply to
HomeBrewer

Specs are: Left Front: Camber = -0.0° specified range = -0.5° 0.5° Caster = 4.5° specified range = 4.0° 5.2° Toe = 0.05° specified range 0.00° 0.10°

Right Front: Camber = -0.2° specified range = -0.5° 0.5° Caster = 4.2° specified range = 4.0° 5.2° Toe = 0.06° specified range 0.00° 0.10°

What does this have to do with the computer controlled cruise control? The cruise should work based solely on the speedometer -or- the wheel speed sensor. Somethig is not programmed correctly allowing it to switch off at 45MPH.

Snoman - I really appreciate any advice here, but you need to work on spelling / typos before posting. I really don't understand some of your info, even when using contextual clues.

Reply to
HomeBrewer

Okay for starters, you always put more caster in right side than left because roads tend to be crowned and you are a tiny bit left side heavy so that with crowns will tend to make it go right and the extra caster takes care of that. Try leaving left side caster alone and increase right caster to 5.0. If it still pulls, take left side down to about 4.0. On the camber, I like to see more here because of lift. Shoot for +.5 on both sides. The negative chamber on right side is also helping it pull too. Toe looks good. If it wants to follow crack after resetting caster and camber I will tell you what to tweak on toe.

It has everything to do with it because cruise control has a lower engine RPM limit because of engine and transmission function. It is this limit that determines the lower limit of it and when you increased tire size without changing axle ratio (which you really need to do here big time) you increased the relative vechicle speed at same engine RPM vs with stock tires hense the higher minimum speed for cruise. Follow now?

Sorry about the typo's. Some times it is me and sometimes it is this wireless keyboard that I am using. Sometimes I press one letter and get another but some of it is me. (I have a big monitor that I sit back from with keyboard in my lap and mouse is wireless too)

----------------- The SnoMan

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Reply to
SnoMan

OK, I'll try to get them to do the corrections - I need to make friends with someone that has a machine, cause I can't afford $59.95 everytime I need to tweak this thing.

I am tracking.....somewhat. I know I need new gears, but I was under the impression that the cruise would work directly with the speedo recalibration. You are saying the cruise control works on engine RPM as well as speed? Can't the dealer program around this?

NP - thanks again for the advice!

Reply to
HomeBrewer

You need to take it someplace where they warrant alignment for 90 or

180 days so you can get them the tweak it. Besides, they did not align it correctly anyway. In the old days when I learned about it from old timers, they would see how the car drove and check what it did and then read the front end and adjust it to correct it based on experiance. Today a alignment tech just follows spec and has no creativety to tweak it correctly because they are not really running the show per say as software is. Also factroy alignement specs are not absolute because of production variances two cars may need to be tweaked differently to do their best and as I said when you lift it, factory specs are a guideline that you build on, not follow blindly.

I guess you are not completely following me here or perhaps I am not explaing it correctly. You cannot program the engine to run cruise control at a lower RPM because the tranny is part of the picture too and it has its RPM input requirements to for minumum speed control and gear and lockup as well. If you want cruise control to work again at lower speed you will have to regear truck (which you need to do any way) as they is no fix otherwise. The dealer programing just fixed speedot. Shifts are happening at same general RPM as before but that RPM yeilds higher speeds in each gear now and I will bet that OD right now is about useless. Your car is acting the same it would if you had stock tires and put taller gears in it.

Keep me posted because I know I can fix the pulling problem once we get your truck dialed in proper. Do not feel bad, when I had my 2000 K3500 aligned for the first time last year, I took it back 3 times at not charge before they got it right (they finally did what I told them to do and it cured it) and it is still good today.

----------------- The SnoMan

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Reply to
SnoMan

now see he's not the only one not following you because his complaint was that the cruise would not work OVER 45 mph. how does minimum speed control figure in?

Reply to
Chris Thompson

That part is easy. With his tall tires with stock gears the engine requires too much manifold pressure to cruise normally and the cruise control will not engage unless the manifold pressure is above a certain level when you select it. (what this means is vacum is too low and cruise is vacum controlled too) Did you get that part? People install large lifts and tires with stock gear and expect a simple programming to fix everything. His lift and tires is a lot and it is overtaxing the drive train and its controls. If he would simply put some 4.88 or deeper gears in it his troubles would go away and it would aslo run a LOT better too. (there is more than just effective gear ratio hear as there is the extra drag from lift and increased rolling resistance of tires too.) What was a good cruise RPM with stock tires and no lift no longer applies and you need a cruise RPM a bit higher now to have more cruise power to overcome this added load. Below is a link to a tire size/axle ratio calculator.

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The SnoMan
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Reply to
SnoMan

That's funny, because my '99 Ram ran just fine with 35x14.5" Mickey's and a

4.5" lift, with the stock gears for a long time. I simply corrected the speedometer with a little electronic box (started with an Abbott ERA, but switched to a Superlift Truspeed when I went up to 38's), and never had a problem with cruise control - it would engage around 37-38MPH, and wouldn't ever cut out (at least to 85MPH or so).
Reply to
Tom Lawrence

Funny thing is you have a older car with older style control and I know it is a slug without riding in it if it has stock gears. My daughter DOHC Saturn would eat it up at higher speeds and my stock K3500 would badly embarrass it at all speeds. I by a truck for power not looks and I would not do any mod that would take that away and no chip or air filter on tune will fix big tires and a lift, you needs gears. If you feel you have good performance that just tell me that yu have lower standards because the physics of it proves otherwise.

----------------- The SnoMan

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Reply to
SnoMan

wait now you talk about manifold pressures. fine I understand about naturally aspirated engines. I do not claim to understand (without researching it further) ALL of the factors the program looks at in order to engage the cruise. whether the MAP is one of those sensors for sure I'm not going to comment on.

ALTHOUGH this has nothing to do with "minimum speed" so I ask again. what does minimum speed have to do with not engaging over 45 mph?

I await an answer that actually has something to do with the minimum speed.

Reply to
Chris Thompson

And another thing... why are you blabbing on and on about engine vacuum? Let me quote you something from the '04 service manual:

5.7L Gas The speed control system is fully electronically controlled by the Powertrain Control Module (PCM). A CABLE AND A VACUUM CONTROLLED SERVO ARE NOT USED. This is a servo-less system. The controls consist of two steering wheel mounted switches. The switches are labeled: ON/OFF, RES/ACCEL, SET, COAST, and CANCEL. The system is designed to operate at speeds above 30 mph (50 km/h).
Reply to
Tom Lawrence

Tom, you are the one blabing here and you think that engien vacum has not effect on been able to use cruise control. If the ECM thinks the engine is laboring too much (MAP and RPM) it will not let cruise engaged but you are likely one of those that want to beleive that truck systems are immune to this stuff. BTW with his current setup he will be turning about 1500 RPM in drive at 45 and a little over 1000 RPM in OD and no "Hemi" is going to what to pull that and the drag with it in cruise control. I could even calculate how much power is required and what is availble but you would think that is BS too because you do not understand any of the physics here only your ego.

----------------- The SnoMan

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Reply to
SnoMan

SnoMan wrote in news: snipped-for-privacy@4ax.com:

I think the vacuum is somewhere else, else?

If the ECM thinks the

Give us a break. You are book smart, but try the real man's world.

Sweet Daddy

Reply to
Sweet Daddy Siki

Well snowman, here is the point that you seem to be missing. IT DID WORK PRIOR TO THE REPROGRAMMING according to the OP and unless a speedo reprogramming somehow changed the load on the engine or the vacuum....

Reply to
TBone

Actually I never tried the cruise before the reprogram...I really wish I had now though!

Reply to
HomeBrewer

You're the one who said, "cruise is vacum controlled too" (spelling mistake and all). I'm simply pointing out that you have no comprehension of the systems you profess so much knowledge in.

But it is engaging just fine... it's suddenly DISengaging at 45MPH. I believe the dealership screwed something up when they changed the pinion factor in the PCM. The only reasons the CC would automatically disengage is if it thought the trans was in park or neutral, if the RPM increased rapidly (like a clutch was disengaged in a M/T vehicle - N/A here), excessive engine RPM (again, mostly a M/T issue), a speed signal that increases 10MPH/s (spinning the tires), or a speed signal that decreases 10MPH/s (vehicle hit something). It will also disengage above 85MPH.

There's zero mention of engine vacuum as a cause of CC disengagement anywhere in the FSM. None. Zip. Nada. The fact that hundreds of other truck owners have upgraded to 35" tires (it's been a very popular upgrade) without issue, also leads me to believe there's something "screwy" with his particular truck.

Actually, 1700 - but let's not nitpick.

Which OD? There's two of 'em, y'know...

So - if you're correct, and it's vacuum-related, he should be able to select manual '2', engage CC at 40MPH, and accelerate via the CC controls up to

50MPH, no problem (that'll start him out at about 2500RPM, and finish up about 3100RPM). If it still cuts out at 45MPH, then what will your answer be?
Reply to
Tom Lawrence

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