Towing improved

[haggus]

I have just had the chance to finally tow with my truck. After the HO water pump, FTB, walbro fuel pump, D-Max, fan, custom tune, and Hayden clutch mods. What a difference at least 20- 35 Kph more speed up the same grades EGT went to 950 F and eng temp stayed below 100 C the whole way kept the RPM in the 2000 -2500 range it's still no Cummins or D-Max but for the first time since I owned this truck I actually spent more time focused on the road than on my gauges.The third gear TCC lock up in the tune is nice to.

The last time I made this trip EGT were fast to 1100+ and temp was over 100 C and power was abysmal I literally couldn't keep 50 Kph going up a hill while towing.

Makes me think how much more benefit I could get out of an ATT or Holset. Not sure what kind of mileage I was getting probably not great but I am sure satisfied with this run it's nice to have some confidence in your ride when towing. Now I must go knock on wood because she will probably friggin detonate on me next time I drive her.

 

[NVW]

Congrats, the mods really make a difference.

 

[Big T]

Makes me think how much more benefit I could get out of an ATT or Holset. Not sure what kind of mileage I was getting probably not great but I am sure satisfied with this run it's nice to have some confidence in your ride when towing. Now I must go knock on wood because she will probably friggin detonate on me next time I drive her.

I came to this here site because of the poor towing performance and overheat problems on our now wrecked '95 Suburban. I bought that truck to tow boats down Baja, but simple local towing showed it to be not up to the task. It would never survive the grades in the Baja heat during August.

After doing just about all the upgrades you have here, the results were impressive. Throw on that ATT and you'll have extra buffer on the heat. It's a cumulative effect of all the changes that really makes the difference. We owe it to all the wrenches on the internet who have learned through trial and error to make these once deficient engines what they really can be.

 

[haggus]

I came to this here site because of the poor towing performance and overheat problems on our now wrecked '95 Suburban. I bought that truck to tow boats down Baja, but simple local towing showed it to be not up to the task. It would never survive the grades in the Baja heat during August.

After doing just about all the upgrades you have here, the results were impressive. Throw on that ATT and you'll have extra buffer on the heat. It's a cumulative effect of all the changes that really makes the difference. We owe it to all the wrenches on the internet who have learned through trial and error to make these once deficient engines what they really can be.

I actually towed a 5th wheel from Victoria to Disney Land down the I-5 before the upgrades only mod was a relocated pmd and the trip wasn't to bad it was August the hills made me think this truck was a dog so I started researching.

It kind of scares of me to think I made that trip there and back without something expensive going wrong. I have a homemade inter-cooler sitting in the garage waiting to go on. I think I will pull the trigger on the ATT in the next couple of months. There are a few things I want to look at first. Since I am running a GM-4 BW right now with the tow tune I push about 10 -12 psi at 2500 rpm. From what I have read the ATT will push the same but allow more throttle keeping EGT about the same.

I also have a new Derale tranny pan to put on adds 3 qt to resevoir and should keep temps relatively low although I have a temp gauge it never goes that high but like I said I am starting to gain some confidence in the truck and the 6.5 TD. If it holds up the future plans will be to acquire a military take out and build up a solid 6.5 replacement motor when this one gets tired.

 

[JiFaire]

Good for you, Haggus!

Hint: If you are serious about the ATT, don't do the intercooler just yet. It is a lot of work that really improves a GMx turbo, but experience is proving an intercooler superfluous with an ATT.

 

[haggus]

Good for you, Haggus!

Hint: If you are serious about the ATT, don't do the intercooler just yet. It is a lot of work that really improves a GMx turbo, but experience is proving an intercooler superfluous with an ATT.

Yea I read the ATT will not require an Inter-cooler. Just depends on my budget I can probably grab a GM-8 turbo cheap at my local wrecker with that an intercooler it might be just the setup I need at the moment.

That being said if I can swing the 1000.00 it will be ATT new oil cooler lines and a oil filter bypass from Leroy.

 

[great white]

Yea I read the ATT will not require an Inter-cooler. Just depends on my budget I can probably grab a GM-8 turbo cheap at my local wrecker with that an intercooler it might be just the setup I need at the moment.

That being said if I can swing the 1000.00 it will be ATT new oil cooler lines and a oil filter bypass from Leroy.

Make sure you examine any used gm turbo very closely at the blade tips, the leading edges and along the axis of the blade for cracks and damage.

Most will have some damage......

 

[haggus]

Make sure you examine any used gm turbo very closely at the blade tips, the leading edges and along the axis of the blade for cracks and damage.

Most will have some damage......

Luckily for me the guy I usually deal with is ex military and he will let me take and examine the parts I grab. He lets me pull the stuff I want. Got to love veterans and to think all it took was for me to get the guy a ball cap off the submarine.

 

[Big T]

Yea I read the ATT will not require an Inter-cooler. Just depends on my budget I can probably grab a GM-8 turbo cheap at my local wrecker with that an intercooler it might be just the setup I need at the moment.

That being said if I can swing the 1000.00 it will be ATT new oil cooler lines and a oil filter bypass from Leroy.

Don't bother with half steps like a GM 8. Save the money and do it right with the ATT.

I have the aluminum finned deep dish tranny pan on the '99. They're nice. New stainless oil lines and cooler are also nice.

 

[haggus]

Don't bother with half steps like a GM 8. Save the money and do it right with the ATT.

I have the aluminum finned deep dish tranny pan on the '99. They're nice. New stainless oil lines and cooler are also nice.

Since everything I have read about the ATT seems to make a huge difference in these trucks I am going to start saving my money again, To many projects I am in the middle of rebuilding my 89 BMW 525I and I just replaced the front end of the truck at x-mas that was a big one it cost me nearly 3k buying my parts locally, but that essentially got me a new front end and it does make a big difference.

 

[haggus]

Well final update on the towing I covered 541 Km on a 100L of diesel that is mixed towing and driving. It worked out to 13.85 mpg and that is mostly highway. I usually don't exceed 52 Mph when towing 65 Mph when driving highway without my trailer. Now to see what a 100 L gets me with the econo tune and no towing I am expecting 15 -18 mpg.

Sorry if anyone is confused by use of metric and imperial units I was raised with both and it is easy for me to convert them.

 

[haggus]

I drove the truck w/o towing just usual DD type mostly. This tank I averaged 17.2 Mpg pretty good overall I think. It will be interesting to see what an ATT, and new injectors might do for the truck.

 

[Burning oil]

Most reports i've heard is a + 3mpg. One reported back at +5mpg, but he did injectors and exhaust all at the same time so what amount ATT contributed ???

 

[haggus]

Most reports i've heard is a + 3mpg. One reported back at +5mpg, but he did injectors and exhaust all at the same time so what amount ATT contributed ???

5mpg would put me in the 22mpg range that would be amazing for a 3/4 ton from the 90's. That would definitely justify the cost of the ATT. I already have the injectors just need to gather all my parts so I can tear it all down at once. I will do the head gaskets while I am in there. That being said I have to leave for a deployment and will not return to x-mas so it will most likely be spring before I can get to the truck.

 

[Burning oil]

5mpg would put me in the 22mpg range that would be amazing for a 3/4 ton from the 90's. That would definitely justify the cost of the ATT. I already have the injectors just need to gather all my parts so I can tear it all down at once. I will do the head gaskets while I am in there. That being said I have to leave for a deployment and will not return to x-mas so it will most likely be spring before I can get to the truck.

You probably wont get 5 more like 3. The guy that got 5 was running really bad injectors and stock exhaust , this was on a dump truck that was worked hard and never mantained til he got it.
Anyway don't get hopes up for 5.

 

[guybb3]

I got a solid 1.5 -2 mpg (minimum) when I put my ATT on