Timmmmmy

Thanks for the replies, I'm going to stay away from this one. Turns out it isn't a dealership selling this like I originally thought. I'll keep looking or just go with new parts. Thanks for the help guys.

Hey Warrior, I really apreciate you posting that. I'll talk to my gear guy and see if he is up to this. If it works I would be getting a locker out of the deal in staed of just a re-gear. This may be a dumb question but could I just instll the diff without hooking up the air lines? Would it function as a normal or would it need to be hooked up? Its my daily driver so if i could instal the gears and notch the bearing first. Worry about installing the pump and running lines afterwards. I can't have the truck down for more than a day or two. Might be an option. for me. Thanks again.

So I spoke with them again. They said it was from a Rubicon and has an air locker. The guy who is a heavy duty mechanic assured me they would fit my 89 D44. But I'm not really sure what it would take to set up the locker. I'm not the most mechanically inclinned and would be having a mechanic do it. Their is a guy who installs (Even used) gears for very reasonable prices. so its an option. It would be nice to have a locker but it sounds like it would be pricey and complicated. Also the previous poster mentioned running 4.10 gears on my current carrier but I beleive the carrier break is below 4.10, I would need a new carrier regardless to run the 4.10's. If its not to chalenging to set the locker up I might consider it otherwise I will let this pass I think.

jeep wrangler TJ DANA 44 diff set complite 4.10 - $180 http://vancouver.en.craigslist.ca/van/pts/4356135080.html I found a Chrysler dealer ship selling this. They said its from a very low KM rear dana 44 axle off a TJ. I am wondering if this diff will fit my factory Dana 44 that came on my 89 Comanche Metric Ton. Now IIRC the only TJ to have 4.10 stock would be the Rubicon, also would the carrier not be lockable? What am I looking at here? Apologies for the lack of better info or if the answer is obvious, not the most knowledgeable in this area. PS you may remember asking gearing questions last year as I was about to pull the trigger and ditch the 3.07's. Long story short thousands needed to be put into the trucks engine and transmission... It was bad year for maintenance and I could only spend so much in a year in my truck. Hoping this might save me some money and let me re-gear this year. Thanks in advance!

Hey guys, sorry I didn't you an update earlier. I went to work the next morning, truck fired right up, no hesitation. I then drove it back to my mechanic. They kept it for a week. Several times a day they fired it up, turned everything on, let it idle. They could not get it to not run. They did every test they could on it and no luck. So I took it home and it has been fine since, till tonight after work, rode the bus again. lucky the mechanic is a friend and i wasn't charged anything. He had a jeep with similar problems and it turned out to be a Crank shaft positioning sensor, not sure it that makes sense. I will get the truck back to him and tell him to check all of cruisers tips. I am tempted to do the alternator regardless. Again driving if I turn the lights on, the dash voltimeter lowers a few centimeters, if I turn on the heat it drops further, almost to red line. Ill update when I can.

Hey guys, for the last year my truck 4.L Renix 89 has randomly not started. At first it happend every few months, then in the last month it has happend about 5 times. Over the last year I have tried to figure this out. It has a new Optima Yellow top, distributer. I have had the aternator, fuel pump starter, and charging system checked numorous times buy a legit mechanic. All check out fine. Up until last month the truck wouldn't turn over at first. I would turn it over 2 or 3 times and then it would fire up. Then last week it wouldn't start at all. I had someone jump me and I got it to run. It ran fine for a week and then today after work it died completly. I had a co-worker jump it and had cables on it for ten minutes. No luck. My truck now sits on the street and I'm on the bus. I started watching the batery gauge in my cluster last week. Often at night when I'm driving I will turn the lights on and the gauge will drop almost into the red. I turn the lights off and the needle goes back up a fair bit. My mechanic checked this out and said he noticed it but that the gauge appears to be not that accurate. Has anyone come accross this before? Sounds like the alternator but my mechanic is telling me that it is working. Any input would be very appreciated. Thanks

Hello, So I recently purchased BFG KM2's 265/75/16 (31.9" X 10.5") and will be putting them on TJ 16X8 Rubican Moab rims. The truck has a RC 4.5" lift in the front and around 5.5" Lift in the rear. The lift said it can fit up to 32" tires but I'm a little skeptical. I'm trying to figure out how these will fit before installing them. I am not sure if wheel spacers and or cutting and bump stops will be required. FYI I would like to throw bushwacker flat flares on eventually but am hoping to avoid wheel spacers. Right now the truck has 245/75/16 (31" X 9.5") and rubs slightly on the RC lower control arms at full wheel lock. If anyone has any experience with this set up or has an idea of how they will fit I would love hear. Thanks in advance, Ryan

I don't think I would be dissapointed either, lots of people run this setup. However if I am paying to set-up gears anyway I am leaning towards the 4.56, especially after looking at the RPM charts and hearing peoples comments. The rear 44 is being re-built regardless and I'm positive I'll get my money back from the D30 with 4.10's I picked up.

Well I'm pretty sure the truck will be getting 265/75/16's and 4.56 gears. I'm feeling pretty comfortable with that setup. It is a shame as I just bought a good used D30 with 4.10's from a guy on my local jeep club board. Fresh gears front and rear will be pricy and it may have to wait a little longer but I want to do it correctly. I appreciate all the help and input. The tires/rims/gears will be more than I paid for truck and that was a big investment. I know the gears/tires question has been asked many times and beleive it or not I have read as many of the threads as I could find. I was still unsure though, largly regarding the drivability of gearing from 3.07 to 4.56/4.88's. So thanks again! Ryan

Eagle: I am going off your spreadsheet stickied in the DIY forum. Granted I am still trying to wrap my head around numbers but thats where I got it from. Also I have read that automatics need/benifit from lower gearing than manuals do. Is there any truth to this?

Eagle, thanks for posting all that, it really helped me to wrap my head around what I was missing One thing though. You suggested the 4.88's based on the 265/75/16 tires having the same revolutions per mile as a 33X12.5X15. From my conversions this is a 31.6" (Most likely smaller than advertised) and I should go off the 31.5X10.5 table on your excel chart. Going off your chart with 4.56 at 70MPH I would be at 2713 in fifth gear, I imagine I would be around 3000 RPM at 75/MPH. This seems to be the best gearing option. Does this sound correct? Also looking at the 31X10.5 chart I notice that say with 4.56 at 70/MPH in 5th gear I would be at 2713/RPM. The 1:1 for this tire size which I think represents 4th gear would be 3618/RPM. As 5th gear is not good for climbing hills, would keeping up high top speed be a problem when climbing hills? Having to climb hills in fourth seems like I would be either going pretty slow or revving very high, is this a correct assumption? It isn't a huge concern as most of my freeway driving is flatish but when I head North I take a very hilly highway. If you have ever seen that highway to hell reality show this is the HWY, the Coquihalla Pass, it has some very long and steep grades. Should I be worried about keeping speed up on hills? Also I havn't calculated my MPG. I'll try to work it out next fill

Funny how I started this thread worrying 4.10's was to deep and now I'm worried they are not deep enough. After looking at the chart I am starting to think 4.10's are to low, at least in principle. I get that if the top speed I am likley to cruise at is around 75/MPH then having the RPMS around 2500 - 2900 is alright. I really like the idea of being able to get into fifth earlier and actually use the overdrive. I do have a few questions though. 1.) I have heard that the ideal RPM for fuel effeciency is around 2250 on the 4.0L. If I'm cruising on the freeway at 2600 - 2900 RPM wouldn't I be getting poor fuel millage? I understand its a Jeep and you don't drive one for economy but it does impact how much I can take it out and how far I can go. I would like to keep fuel costs as reasonable as possible. 2.) I know it has been said that running even as high as 2900 RPM isn't bad for the engine but I can't help think that driving at that level for extended periods must put additional ware on the engine. Keep in mind I travel over an hour at that speed on the freeway. Several times a summer I head North and could be running at those revs for four plus hours straight. Can I be sure this isn't having an impact on the engine? 3.) Forgive my ignorance but this is my first manual vehicle and I have only driven on 31's with 3.07 gears. Would driving with this low of gearing (4.56) be comfortable as a daily driver? I guess I'm thinking of having to start in second or it just being awkward to drive in town. I'm worried I won't like how it drives. At this point I am thinking of going with 4.56 gears on the 265/75/16 BFG KM2's I have picked out. I am pretty nervous though. If anyone has any experience of daily driving with a similar setup or can answer any of my concerns it would be very much appreciated. Ryan

In terms of revolutions per mile (which is the only important criterion when matching gears to tire size), the 265/75-16s are identical to 33x12.50-15s (637 revolutions per mile vs. 636 revolutions per mile). Using that as the base, my speed to RPM chart (which is corrected for actual revolutions per mile, not theoretical tire diameter that doesn't accound for sidewall squat), I get the following (in 5th gear): 4.10 gears ==> 2282 RPM at 70 MPH (my chart doesn't go up to 75 MPH) 4.56 gears ==> 2538 RPM at 70 MPH 4.88 gears ==> 2716 RPM at 70 MPH Crunching the numbers, to convert that to 75 MPH we get: 4.10 gears ==> 2445 RPM at 75 MPH 4.56 gears ==> 2719 RPM at 75 MPH 4.88 gears ==> 2910 RPM at 75 MPH You should be changing to 4.88 gears. 75 MPH cruise at 2900 RPM is NOT pushing the engine too fast. Conversely, 4.10 gears isn't nearly enough gear for those tires. Remember, a "31x10.50" tire is NOT 31 inches in diameter -- they are typically between 30.3 and 30.5" overall diameter. So if you're thinking that your chosen tires are close to 31s ... you're wrong. If you're not comfortable with 4.88s, go with at least 4.56 gears. Putting this is perspective, a stock XJ with automatic and 225/75-15s turns 2261 RPM at 70 MPH, so if you go with 4.10s you're getting exactly the same final drive ratio as a stock vehicle ... but you're trying to spin much larger and heavier tires. Hmmmm. well you certainly have given me a lot to think about. I have heard the KM2's are a true tire size compared to other makes but that could very well be heresay. From what I have read the KM2 265/75/16 is 31.9" but on a 8" wide rim it sits at 31.5. At any rate the RPM breakdown is very helpfull. I was thinking running the engine at close to 3000 rpm was on the high side as 2250 was the sweet spot for the 4.0. I have some thinking to do, your input is much appreciated Eagle!

Yeah thats what I thought. I remember hearing that 31's and 4.10 was a good combo. I was just worried that it would be great for wheeling but a dog on the highway. One of the guys at work who is a huge car guy just re-geared his durango to 4.10's and said its pretty slow now but the acceleration is good. I think 31.5s are fine for me at the moment as well. I would be going bigger for the sake of going bigger. Anyway thanks for the input. Very much appreciated!

So I will be picking up tires and re-gearing pretty quickly. I am hoping to get some opinions on the right setup for my needs. Truck: 4.0, Manual, 4X4, 4.5" lift up front, 5.5 in the back, 3.07 gears, D44 in the rear Use: Daily driver in semi hilly area, camping and wheeling requires an hour on the freeway, needs to cruise comfortably at 120/KPH or 75/MPH. Trails are very steep and usually wet. I really don't wheel that hard, just getting into it. I had settled on 4.10 gears and 265/75/16 (31.9 - 10.5") BFG KM2's (Have ring/pinion/carrier etc for my D30 already) I am having second thoughts for a few reasons: 1.) My mechanic and other people have said this might be too low of gearing for highway driving, too slow 2.) Wheeling buddies have said to just go with 33X11.5 The reasons I am considering the 31.5's is because they should fit my lift without fender flares and wheel spacers and because I assume it will help reduce fuel consumption So I guess I'm wondering if: 1.) 4.10's and 31.5's will be to low for highway use 2.) Whether I should just go with 33's and put cut out fender flares and or 6" coils in. Will this really increase fuel use that much? Any advice is appreciated, I just want to make sure I get it right the first time, can't afford to do it twice, Ryan

Thanks, I just wasn't sure that perticular battery would clear the hood, thought it might be to tall. Thanks for the help!

Hello, I have the opportunity to pick up an Optima yellow top battery at a good deal. Does anyone know which size battery will fit best in the stock tray? I'll be running a Warn M8000 winch and a CB FYI The optima web site is kind of strange... When you do a make and model search there is no comanches listed and the first year cherokees show up is 98 The recomended yellow top battery for a 98 cherokee is a OPTIMA® Batteries 8014-045 D34/78 YELLOWTOP® Starting & Deep Cycle Battery Dimnensions are Length: 10.06 in Width: 6.94 in Height:7.88 in Is this a good choice?

FYI the "Crunching" sound I was hearing was the result of a shot tranny mount.

Thanks for the info mnkyboy, very much appreciated. I think it will depend on what I can find in the junkyard. I will start the search this weekend. I hear what your saying with it not designed for the one piece shaft, I will try and avoid it. Good to have the seal number none the less if I do go that route. FYI I read your build thread. I really like what you did with the truck, looks great. I'll be watching the thread.

Thanks guys. I think picking up a new axle will be cheaper and easiest for now. Re-gearing the current axle will require new ring & pinion, carrier and labour. I'm thinking of finding a geared axle of the similar CAD style and swapping it in. When the joints go on the new axle I will do the shaft swap to get the bigger U-Joints. I have been looking for a good write up on the axle shaft swap, can't seem to find one. I have read that you need to change the seal for the passenger side axle when converting a CAD axle to non disconnect axle shafts, they are a different diameter. Can anyone point me in the right direction. Would this be the only thing needed to change when swaping shafts?

Thanks guys, thats what I was looking for. Not sure why but when I hit paste it cut out the 4's.... Should read 4.10's. I am hoping for a 96+ D30 because they have the bigger U-Joints. I have just figured out however that I can swap just the shafts in from the newer D30 and get the bigger joints. I may go this route, swap shafts, re-gear, and keep the origional axle. Thanks!

So my U-Joints are going on my 89 comanche 4x4 manual, non abs, CAD vaccume disconect axle and I figure this is a good time to start the re-gearing process. I am looking to swap in a dana 30 with 4:10 gears, the question is which one. Option one: Find an axle from a similar year with 4:10 gearing and with non abs, and CAD vaccume disconects. This would be easiest. Option two: Find a 96-99 dana 30 from a cherokee, these are NON CAD vaccume disconect and have the larger 297x u-joints From what I understand option two would give me a stronger axle. While it will bolt right on, the problem is I havn't found a good write up on this addressing the issues of what to do with the vaccume hoses and potentialy having the axle set up for ABS. Anyone done this swap? have a good idea of the swap difficulty and whats involved or can send me a link? Also as funds are tight I would like to do this in two parts, front axle swap first, re-gear my rear 44 that is installed second. Can someone confirm that as long a I don't engage 4WD I will be able to drive it with miss-matched gears? Thanks, Ryan

Well I have been pondering this one for a while. My 89 has 255,000 KM on it but runs strong. The day will come however when it finally tuckers out and it will have to be replaced. I want the truck to remain as origional in every way possible. All the upgrades I have done and plan on doing are in this spirit. I would love to re-build the engine when it goes and keep all the vin numbers matching. That being said though I will most likley have this truck for at least the next 15 years and sticking with the renix block will have its issues. The biggest concern for me is the continuing availablity of parts like sensers, belts, wiring components etc... The H/O had such a good run I can't help but think it will be a far more practicle engine to maintain over the coming decades. Obvously it is possible to maintain the Renix engine for a long time to come but is it worth it? Will the practicality of switching to H/O eventually prevail and when do you see this happening? Ryan

Thanks guys!

Hello, I just picked up my Rough Country Cherokee front bumper for my MJ. It looks like I will have to trim the forward portion on the front fenders and plastic trim flush with the bottom of the front clip/header for it to fit. I have never trimmed metal before and want to make sure I do it properly. Should I simply cut it flat or roll the edge over? I have tried searching online and on CC for a write up doing it as well as removing the front bumper and skirt but haven't found much. If you know of a good link it would be much appreciated. Thanks, Ryan.