Exhaust brakes

I'll keep it short also.
No personal experience but the feedback I've received is they're poisonously expensive for what you really achieve .... besides you can't actually use them in towns to show off can you?

CheersFidei defensor

Rosco

Being a former(?) truckie, I ask "why" would you want to fit any sort of engine retatrder to a 4X4. In low range, in low gear descending a hill you get an awful lot of engine retardation. In my mind there is absolutely no logical reason for fitting a engine retatrder (exhaust brake) to a 4X4. Sorry for being so blunt, but it just doesn't make sense. I've 4X4ing since the late eighties and I haven't seen a hill yet that would require more retardation than 1st gear, low range would give.

Wayne,
I've thought about it too from time to time. I remember many years ago (around 1994) one of the magazines did a review on the one available from northern qld (around $1100- I think). They said it was very good when tested going down a long winding hill (like many on the eastern side of the Great Divide, from Atherton to Dandenong) and saved the driver of a 4x4 with a heavy horse float or van from having to use the foot brake as much.
I have a turbo 4.2 Patrol with 3" exhaust....not sure what the back pressure would do to the turbo housing etc. ...I would imagine there would be a fair bit of additional pressure which may cause problems. Might pay to phone the mob in qld, ask them if they have satisfied customers who could give a testimonial (but watch out they could be stool-pigeons!!!???).
My thoughts have been centered around getting one off a wrecked light tipper or similar.
A mate of mine said the Patrols (GQ) they used in underground mines at Broken Hill used to have exhaust brakes fitted....he has a mate who bought one cheap and the only thing that wasn't totally stuffed was the brake...
Cheers,
Roachie

I think it is important to remember the primary reason for using an engine retatrder is to HELP maintain a constant speed while descending a hill. BTW I live in country Victoria, not a capitial city!! So I know the bush.

I have been a heavy vehicle driver trainer since 1987. Working with many national and international tranport companies, so the information I give is well tested. The information I will give below I will relate to 4 wheel drives, not trucks.

1. The important part of descending any hill is to have the correct gear selected before you go down, it is always best to have a lower gear than necessary if you ar unsure on the steepness of a hill.

2. It is always best to go down a hill without using brakes, but we all know this is not always possible.

3. For those times when it is not possible to go down a hill without using the brakes and when you have an engine retarder turned on (in 2 wheel drive) you are slowing down your drive wheels (normally rear), if you put your foot on the brake you have all wheels working as brakes, in normal terms this means 2 wheels (with engine reatrder), versus 4 wheels or more with a horse float (that would be required to have brakes on, either electric or hydraulic over cable) with your foot on the brake.

4. There has been extensive testing about which is the best way to use brakes when going down a hill, one thought was slow steady pressure all the way down the hill is the best method, and this was taught to truckies for years, but the general consensus these days is the let the revs SLOWLY(see note below) build to engine governed speed (remember it is only at high reves that you get the best engine restrdation) and then gently apply brake pressure till the revs drop down fairly low, then let the revs build a again (remember what I said in my first post, that when 4X4ing I yet to come across a hill that 1st gear low range won't cope with (although I am sure there are some), but generally there aren't too many.

NOTE: If you have a very low gear slected then the revs WILL build slowly, if you are in a too high a gear, then the revs will build fast. Most people (particularly in urban driving) want to go down hills FAST, not SAFELY.

5. Engine retarders were designed for heavy vehicles, but some manufacturers have modified the idea for 4X4s.

6. If you see truckies using engine reatrders on flat ground they are doing it for show, not for practicality. They will get some retardation, but not as much if they put their foot on the brake (2 axles with retarder, versus 6 axles with foot on the brake.)

Wayne if you drive in hilly terrain all the tim, might I suggest that if you go down a hill in 3rd and you have use the brakes too much, then go down the hill in 2nd with the revs up high, I am sure you will be surprised at the results, in fact keep an eye on your speedo in both circumstances and you will probably see not much difference in road speed.

Good Luck.