Since first owning my 03 STR I knew there was an issue with the transmission. Shifts were harsh, slow to downshift, horrible lurch, fluctuating rpm's till fully warm, and intermittant "Gear Box Fault" message. Though the car impressed me with power and speed, there was "something" missing in the power dept. From warmed up there was impressive power, then noticeably less when very warm. Much of this I attributed to heatsoak, especially with the 3 lb pulley. 6 months ago, when 125k miles came, a warranty was applied to help address the inevitable. This helped to economically replace a fuel pump/fuel sender switch to solve abscent fuel gauge reading, and a recent trans. and torque converter rebuild. Post rebuilt trans./TC rebuild made for smooth shifting but precipitated an intermittant shudder when in high gear against a load with moderate gas pedal depression, partially diminishing with a downshift from deep depression of gas pedal. No CEL or fault messages. The trans. shop checked it over and came back with nothing wrong. Last night the indy Jag mechanic hooked up his official Jag diagnostic code/reflash machine. Approx. a dozen old codes popped up including TCM related. The codes were cleared and he ran a check again with no repeating faults or codes. He then reflashed the TCM and advized driving a few hundred miles then perform another diagnostic check. He said the storage of several old codes can inhibit performance. The 15 mile ride home was exillerating. The first 8 miles was driving normal in normal mode, shifts were smooth and higher up in the rpm band. Shuddering wasn't detectable, but let's put some more miles on before declaring victory. Last leg was on the highway in Sport mode DSC off...power was everywhere. From a dig the tires could not be helped from roasting and the limiter was popping on and off through third gear, possibly into fourth, very violent acceleration, like an entirely different personality from the pre-trans/TC rebuild. Top-end charges were strong with good downshift points. For track duty this STR requires an LSD differential. Took her for a ride this cold NY morning and what a thrill! Smooth shifts and power everywhere. Happy.

 

Good to hear that. Transmission problems are the worst to deal with.

 

Well done! Looks like you and I are on the same path... I just got mine back about 500 miles ago from the same full front to back transmission rebuild, I didnt have the warranty so it was a hard hit to the pocket book, but worth every penny!

I completely agree, once I got mine back with all new steels, clutches, valve body and TC it was like a completely different car, no more lurch, no more hunting for gears, no more vibrations and best of all heart stopping launches with much improved higher rpm shifts!!

Best $5000 ever spent on this car! Now lets the perfomance mods roll, just ordered the caldoofy intake this afternoon so should give me an even tighter throttle response and quicker launch!

Cheers!

 

cbharley hit the nail on the head on the cost of a ZF trans. rebuild. AMMCO charged the warranty company $7100 for parts, trans. and TC rebuild, and labor. cbharley, after the modded air intake tube pop on a smaller pulley, Magnaflow hi-flow cats and Tru-X center muffler. Stop here and see how you like the sound of the exhaust or install Dynomax VT mufflers if you want more flow and less drone.

 

Yeah the ZF rebuild is a real zinger on the wallet, but will definitely put a smile on your face once you get back on the road! At least we have another 150K miles to enjoy that spend!!

Thanks for the tip, after all of the not fun expenses for standard maintenance its nice to finally be able to start putting some $$ into something fun! I am anxious to see how the Mina Intake with the new aluminum elbow perform. Should be interesting to see if those combined 30ish horses make a difference. The immediate throttle response alone has me "geared up" to continue on my quest for a 500+ HP 03 STR.

bfsgross, you have any links you can share for the exhaust I like the idea of the new X pipe and was thinking I wanted to go full cat back on the performance exhaust. I know there are a couple of options available with magnaflow etc for the performance cats. I was thinking about the Mina performance exhaust but is only the connector pipes and the mufflers so would definately need to piece that system together. I am certainly open to other suggestions / ideas and would like to do some reading on the system you have mentioned. From the looks of it you are running that system yourself how has it worked for you performance and sound wise?

Finally what did you do for the pulley? Did you take it in to a speed shop or was it something you were able to do yourself? I have read several write ups about the horrors of replacing the SC pulley. I was actually thinking that since I have over 140K on the clock it may be wise to just pull the snout off and rebuild the whole front of the blower. I dont have any issues as of right now, but if I am going to change the pulley anyway why not just pull the whole thing out and "refresh" it all...

The old addage applies I suppose " hood's up, do the work"

 

I'm interested in learning more about this warranty? My '03 STR has 125k on it. Right now, runs like a top. But I put miles on pretty fast, so I'd like to prepare.
tell me more about the warranty?

 

cbharley, an indi Jag mechanic ground down the snout and pushed on 3 lb pulley. Pull the blower and send it to Stiegmier to be rebuilt, ported and installation of 3 lb pulley ($750 ?). Maintain the stock 2.25" pipes but install Magnaflow's hi-flow cats ($165 pair) and Tru-X center muffler ($80?), and Walker's Dynomax VT mufflers ($200 pair). These are the next mufflers for my STR. Mcjaguar, there are numerous warranty companies. I'll provide info. in a few hours. It's $4000 spread out over two years at $160/month. It sure came in handy.

 

Mcjaguar, I'll post warranty info. today.

 

bfsgross - Glad to hear your kitty is growling down the highway again... I could have sworn I heard your tires scorching the NY pavement all the way across the Hudson...

 

One word of warning on warranties and mods. Work with a tech/shop that is mod friendly for one. Second, a pulley is had to spot unless you know what youre looking for but other mods like intake and exhaust can cause an extended warranty inspector(they always inspect when repairs go over $1000-1100) to look closer and you can have an arguement about mods and damage to things like trans or engine. And theyre not governed by the same laws as factories and dealers by the magnuson moss warranty act. Read "exclusions and modifications" clauses very carefully in the contract and talk to your shop/techs about these issues. They many times know the inspectors and companies well and can guide you on specifics. We do

 

bfsgross - do you have any part numbers for those I am trying to look them up during my "holiday break" and want to make sure I am looking at the right thing. I found some of the Magnaflow cats but they are 6.5" wide I remember reading somewhere that the cats needed to be around 5"... Also by the x center muffler are you talking about the Maganflow Crossover X Pipe?

 

I have the part numbers in the car. I'll post them tomorrow a.m. In the meantime, you can procure them by using the forum search feature. There's numerous posts listing part numbers of modifications.

 

I'm pissed in 2007 they changed the tune in the TCM or something. I can floor the gas from a dead stop and it will NOT spin. I remember test driving an '05 R back when they were new...and it would totally roast them off a dead stop. Any chance you could point out what trans tune you had?

 

08ZO6, To the best of my knowledge the STR's TCM hadn't recieved a re-tune? What you describe as trying to fry the tires from a dead stop; plagued mine too. Be sure the trans. is in Sport mode and DSC off. If this doesn't do the trick then hook her up to a Jag specific diagnostic reader to draw out faults and codes (there may be none). After clearing, re-flash the TCM. I attribute this procedure for a phenomenal improvement in low end grunt and shift sequence. Soon, the TCM will be flashed with a file for the 03 XKR provided by Mafioso. He professed all shifts reached redline.

 

cbharley, use the same Magnaflow hi-flow cats as quartzstr (2.25"). I purchased components from Summit Racing. Magnaflow Tru-X muffler: MPE-11385 (2.25"). Maintain the original (2.25") stock piping. You may want to maintain the stock rear boxes or choose Walkers' "Dynomax VT" mufflers. These supposedly minimize interior drone and what is next for my car.

 

mcjaguar, my warranty company is: Auto Assure, LLC. Phone: (800) 400-6092. They warranty up to 225,000 miles.

 

Just a thought but do you have some sort of real-world check that your car is producing roughly the right amount of power?

We have had cars fitted with restricters of various kinds, which were found more or less by accident.

 

Seems like ever trans issue i've seen has been on 03 04's. Is this a specific 03 04 problem

 

The 03-04 STR's are older and have more miles.

 

I would second the comments of bfsgross... It seems like the transmission issues start to rear their ugly head just after the 100K mark. I started having "symptoms" right about that time and they just progressed until the "slip...bump" got to be too much to bear. The final straw for me was the terrible slip into 6th at high speed which started a few months back at 140K...

Its not a cheap fix but man... I think the replacement parts are actually better than the stock because the old girl is really like a whole different car at least from what I can tell so far. I have only put 500 miles on the new gear box, but despite the costs I sure got my money's worth in smiles per mile!