There's been a few threads discussing folks tuning their GL450 / 550s.

The main tunes discussed were Renntech ($2740) and OE Tune ($955 special).

I had contemplated the OE Tune early on but that tune seemed relatively unproven without dyno back up - and to be honest a few folk on here scared me off from it.

Not sure if fabbrisd1 is out there to weigh back in - but he had mentioned that he felt the above tunes were overpriced and we should start to see some Euro tunes appear that are better priced for the performance.

I decided to wait - but now we've started to discuss the next model year - thought I'd check with the audience ....

Was wondering who those shops may be (fabbrisd1?) and if anyone had heard anything recently on this front?

 

Any tunes for the GL350 diesel?

 

The Trocore ECU's that MB uses are actually quite straightforward to read/rewrite.

GL350BT - I would recommend Oliver at Speed Tuning USA - one of his personal cars is a 2012 E350BT - info@speedtuningusa.com - he has a amazing BT tune..

If I had a gasser, I would shoot him a email as well, and see what he has to say..

Like around $500 for the tune.. Oliver is a straight up guy, not like some of the West Coast flap jaws.. Oliver will give you straight info on what to expect as realistic result...

Keep the beat !

 

Thanks - will do. I thought a while back you had mentioned some Euro tuners also?

 

I've talked / emailed with Oliver from Speedtuningusa now for a month or so. Sounded promising at first, but still unable to get a tune for the GL450.

 

I am actually getting my ECU back today and will start a thread with the results and my thoughts once I get it popped back in and drive it.

I spoke with OE, Eurocharged, Renntech and Oliver from Speedtuning. Tried to contact Kleeman and never received a response. I decided to go with Eurocharged. What went into my decision was: reliability/quality, performance and cost. Renntech seemed to have the most experience and the largest shop but they are the most expensive. Cost alone wasn't my only criteria so I kept them in the running. They definitely know what they are doing. I spoke with Oliver at Speedtuning and they are cheap (around $500) and he sounded nice, but he was sure if he could do the GL450 because of possible "encryption" which all the other tuners seemed to scoff at and said they would have any problems at all. The guys at OE also were very nice. Ultimately I decided on Eurocharged. The combination of experience, responsiveness and price was great. I think I would have been comfortable with OE and Renntech but chose Eurocharged. As I said I will post back in a few days when I've had a chance to evaluate.

Anyone considering a tune and comparing the above tuners should note that most uners are consistently running really great specials and discounts so you really need to call them and see if they will honor a past discount or when their next special will be. That is the only way to truly compare cost and evaluate whether it's worth it to you. I was able to get Renntech to discount by only 5% which isn't much especially giving what their starting point is.

 

With Renntech, you will get a much better deal through their dealers. They also consistently produce the most power with their tunes. Renntech really goes above and beyond with their customer service. If you ever have any problems, you want to have it with their products. There are so many tuners on this forum and I've heard too many horror stories on most over time but I've never heard a bad word spoken about Renntech. For me, I'm not going to try and save a thousand dollars when modifying an $80,000 car. I want to work with the best in the business and not someone who is cheapest.

I have no experience with Eurocharged either good or bad so I'm not bashing your decision. Just giving another view point. I hope your tune performs great.

 

Sounds like a fun day! Please report back.

What performance numbers did they give you and how much did it cost (if or don't mind me asking)?

 

BlownV8, I completely agree with your points. You have to feel very comfortable with anyone who is handling your vehicle. Whether it's for an ECU tune or a tune-up! I have had issues with mechanics, even at dealers, doing things to my cars that I couldn't believe. Things happen but you want to mitigate the potential for issues and have recourse in the event things go wrong. At the end of the day I did a lot of research, I spoke to the various tuners, I inquired as to what was getting tuned, etc. and then I made my decision. I would agree with you however that if you don't mind spending a premium and just want to go with the guys with a lot of history, experience and positive customer service, go with Renntech.....but make no mistake you are definitely paying a large premium for it. Last point, I don't think this particular tune carries a lot of risks or concerns. When you have someone changing turbos, pulleys, cats, intercoolers, pipes, etc., then you are taking things to a level that really requires you to be very careful for a whole host of reasons. This tune however is really pretty simple and straightforward. This turbo engine is in its first release year and is massively detuned. MB wanted to a.) separate perf. from the 550 and b.) leave themselves plenty of room over the next 5-7 years to simply tweak the software each year to release more ponies and torque. So a tuner can simply go into the software and adjust the mapping, boost pressure and unleash all of that power right now, without much risk (in my opinion). I think the real risk lies not in the tune itself but whether something happens to the ECU in transit or while they are attempting to make the modification since it does need to be drilled (even by Renntech)....I don't think anybody is prying these wafers apart anymore because the risk of snapping them is high. Another issue is if the dealer has to update your ECU (because of an important update/recall) then you will have to send the ECU back to the tuner to be updated again and you want to make sure that tuner will still be around and will do it for free (this will be the same no matter what tuner you use). The last risk, which I don't really consider a risk, is if the dealer were to void your warranty because of your tune IF something were to go wrong with your vehicle. My personal opinion is that a.) if something goes wrong with your vehicle down the road, it won't have anything to do with THIS tune and b.) they don't give people a hard time with simple tunes but rather major modifications (in my experience).

I think the dealers and manufacturers want people to be scared. They would rather people trade in their vehicles when they want to upgrade their engines. They want to make tuning appear very dangerous and like risky black magic that only "race nuts" do. That's all nonsense. I have had a few high end vehicles (carefully) modified over the years and not to make them racers but to release more of their potential and make them a bit more aggressive. Most vehicles are designed for the masses (except supercars) so they dial (way) down the aggressiveness.

In my opinion this particular engine, the 2013 GL450, since it is a twin turbo (turbos always have much more upside tuning potential because of the ability to adjust boost pressure) and since it is in its first year release and is DEtuned, has the most potential for tuning than any other engine I have seen. There is just a ton of HP/TQ that is sitting on the table waiting to be unlocked and for me it is a no brainer to do it. Not to turn a GL450 into a street racer but to allow the engine to give you the snap and power you want (when you want it) at the low range (getting on highways, at a light, passing, etc.).

I will follow-up with results in a few days. The returned ECU is now sitting on my desk!

 

Can't wait to hear. It should be awesome.

When Renntech tuned my CL 600, I picked up an additional 125+ RWHP which was beyond their promised hp gain. The car went from slightly less than 500 hp to around 640 hp. It completely transformed the car.

 

That's a lot of ponies! Yeah I'm really looking forward to plugging this back in. I also have some new spark plugs (high perf and 1 step colder) and K&N air filters I have to figure out installing as well.

I will give my initial thoughts after I slap this back in tonight but will eventually follow-up with pics and videos.

 

Same for my '04 SL600. Much more willing with better throttle response. She went like a bat out of hell with the quiet/smoothness of an electric train!

The gains expected on new GL63 won't be as significant but, I'm sure more pleasurable and responsive around town.

 

I figured I would start a separate thread to give all the details but just wanted to report back that I put the ECU back in last night and so far (can't really push it hard yet) it is INCREDIBLE. Totally different beast.

 

Let us know, I'm going with oetunning good group of guys and will customize the tune to my wants/needs LOL. Here in sunny Florida we have no emissions checks and 93 octane lets see what we can come up with, will report back

 

That's great I can't wait to hear how the OE tune is. They were my 2nd choice. I have my initital write-up done but haven't figured out yet how to post pics. I guess you can't post them on this server but have to post a link to them somewhere? I'm just getting the hang of this board (again) so sorry for the noob ques. I'll do a search and figure it out and get my review up.

 

I finally got my initial review done and posted some pics. It's a bit long....
https://mbworld.org/forums/gl-class-...ml#post5717931